National Library of Energy BETA

Sample records for transition metal oxides

  1. Nanostructured transition metal oxides useful for water oxidation catalysis

    DOE Patents [OSTI]

    Frei, Heinz M; Jiao, Feng

    2013-12-24

    The present invention provides for a composition comprising a nanostructured transition metal oxide capable of oxidizing two H.sub.2O molecules to obtain four protons. In some embodiments of the invention, the composition further comprises a porous matrix wherein the nanocluster of the transition metal oxide is embedded on and/or in the porous matrix.

  2. Superconductors and Complex Transition Metal Oxides for Tunable...

    Office of Scientific and Technical Information (OSTI)

    Superconductors and Complex Transition Metal Oxides for Tunable THz Plasmonic Metamaterials Citation Details In-Document Search Title: Superconductors and Complex Transition Metal...

  3. Transition Metal Oxide Alloys as Potential Solar Energy Conversion Materials

    SciTech Connect (OSTI)

    Toroker, Maytal; Carter, Emily A.

    2013-02-21

    First-row transition metal oxides (TMOs) are inexpensive potentia alternative materials for solar energy conversion devices. However, some TMOs, such as manganese(II) oxide, have band gaps that are too large for efficiently absorbing solar energy. Other TMOs, such as iron(II) oxide, have conduction and valence band edges with the same orbital character that may lead to unfavorably high electronhole recombination rates. Another limitation of iron(II) oxide is that the calculated valence band edge is not positioned well for oxidizing water. We predict that key properties, including band gaps, band edge positions, and possibly electronhole recombination rates, may be improved by alloying TMOs that have different band alignments. A new metric, the band gap center offset, is introduced for simple screening of potential parent materials. The concept is illustrated by calculating the electronic structure of binary oxide alloys that contain manganese, nickel, iron, zinc, and/or magnesium, within density functional theory (DFT)+U and hybrid DFT theories. We conclude that alloys of iron(II) oxide are worth evaluating further as solar energy conversion materials.

  4. Synthesis of transition-metal phosphides from oxidic precursors by reduction in hydrogen plasma

    SciTech Connect (OSTI)

    Guan Jie [Department of Catalytic Chemistry and Engineering, State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116012 (China); Wang Yao [Liaoning Key Laboratory of Petrochemical Technology and Equipments, Dalian University of Technology, Dalian 116012 (China); Qin Minglei; Yang Ying [Department of Catalytic Chemistry and Engineering, State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116012 (China); Li Xiang [Department of Catalytic Chemistry and Engineering, State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116012 (China); Liaoning Key Laboratory of Petrochemical Technology and Equipments, Dalian University of Technology, Dalian 116012 (China); Wang Anjie, E-mail: ajwang@dlut.edu.c [Department of Catalytic Chemistry and Engineering, State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116012 (China); Liaoning Key Laboratory of Petrochemical Technology and Equipments, Dalian University of Technology, Dalian 116012 (China)

    2009-06-15

    A series of transition metal phosphides, including MoP, WP, CoP, Co{sub 2}P, and Ni{sub 2}P, were synthesized from their oxidic precursors by means of hydrogen plasma reduction under mild conditions. The effects of reduction conditions, such as metal to phosphorus molar ratio, power input, and reduction time, on the synthesis of metal phosphides were investigated. The products were identified by means of XRD characterization. It is indicated that metal phosphides were readily synthesized stoichiometrically from their oxides in hydrogen plasma under mild conditions. - Graphical abstract: Metal phosphides were obtained stoichiometrically from their oxidic precursors by hydrogen plasma reaction under mild conditions.

  5. Band gap tuning in transition metal oxides by site-specific substitution

    DOE Patents [OSTI]

    Lee, Ho Nyung; Chisholm, Jr., Matthew F; Jellison, Jr., Gerald Earle; Singh, David J; Choi, Woo Seok

    2013-12-24

    A transition metal oxide insulator composition having a tuned band gap includes a transition metal oxide having a perovskite or a perovskite-like crystalline structure. The transition metal oxide includes at least one first element selected form the group of Bi, Ca, Ba, Sr, Li, Na, Mg, K, Pb, and Pr; and at least one second element selected from the group of Ti, Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zr, Nb, Mo, Ru, Rh, Hf, Ta, W, Re, Os, Ir, and Pt. At least one correlated insulator is integrated into the crystalline structure, including REMO.sub.3, wherein RE is at least one Rare Earth element, and wherein M is at least one element selected from the group of Co, V, Cr, Ni, Mn, and Fe. The composition is characterized by a band gap of less of 4.5 eV.

  6. Electrocatalytic Activity of Transition Metal Oxide-Carbon Composites for Oxygen Reduction in Alkaline Batteries and Fuel Cells

    SciTech Connect (OSTI)

    Malkhandi, S; Trinh, P; Manohar, AK; Jayachandrababu, KC; Kindler, A; Prakash, GKS; Narayanan, SR

    2013-06-07

    Conductive transition metal oxides (perovskites, spinels and pyrochlores) are attractive as catalysts for the air electrode in alkaline rechargeable metal-air batteries and fuel cells. We have found that conductive carbon materials when added to transition metal oxides such as calcium-doped lanthanum cobalt oxide, nickel cobalt oxide and calcium-doped lanthanum manganese cobalt oxide increase the electrocatalytic activity of the oxide for oxygen reduction by a factor of five to ten. We have studied rotating ring-disk electrodes coated with (a) various mass ratios of carbon and transition metal oxide, (b) different types of carbon additives and (c) different types of transition metal oxides. Our experiments and analysis establish that in such composite catalysts, carbon is the primary electro- catalyst for the two-electron electro-reduction of oxygen to hydroperoxide while the transition metal oxide decomposes the hydroperoxide to generate additional oxygen that enhances the observed current resulting in an apparent four-electron process. These findings are significant in that they change the way we interpret previous reports in the scientific literature on the electrocatalytic activity of various transition metal oxide- carbon composites for oxygen reduction, especially where carbon is assumed to be an additive that just enhances the electronic conductivity of the oxide catalyst. (C) 2013 The Electrochemical Society. All rights reserved.

  7. Thermodynamic Investigations of Lithium- and Manganese-Rich Transition Metal Oxides

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Vehicle Technologies Program Thermodynamic Investigations of Lithium- and Manganese-Rich Transition Metal Oxides Wenquan Lu (PI) Qingliu Wu, Dennis Dees, Kevin Gallagher, Ira Bloom, and Anthony Burrell Electrochemical Energy Storage Chemical Sciences and Engineering Division Argonne National Laboratory This presentation does not contain any proprietary, confidential, or otherwise restricted information Vehicle Technologies Annual Merit Review and Peer Evaluation Washington, D.C. May 13th - 17th

  8. Correlation effects in (111) bilayers of perovskite transition-metal oxides

    SciTech Connect (OSTI)

    Okamoto, Satoshi; Zhu, Wenguang; Nomura, Yusuke; Arita, R.; Xiao, Di; Nagaosa, Naoto

    2014-01-01

    We investigate the correlation-induced Mott, magnetic, and topological phase transitions in artificial (111) bilayers of perovskite transition-metal oxides LaAuO3 and SrIrO3 for which the previous density-functional theory calculations predicted topological insulating states. Using the dynamical-mean-field theory with realistic band structures and Coulomb interactions, LaAuO3 bilayer is shown to be far away from a Mott insulating regime, and a topological-insulating state is robust. On the other hand, SrIrO3 bilayer is on the verge of an orbital-selective topological Mott transition and turns to a trivial insulator by an antiferromagnetic ordering. Oxide bilayers thus provide a novel class of topological materials for which the interplay between the spin-orbit coupling and electron-electron interactions is a fundamental ingredient.

  9. Method of synthesizing a plurality of reactants and producing thin films of electro-optically active transition metal oxides

    DOE Patents [OSTI]

    Tracy, C.E.; Benson, D.K.; Ruth, M.R.

    1985-08-16

    A method of synthesizing a plurality of reactants by inducing a reaction by plasma deposition among the reactants. The plasma reaction is effective for consolidating the reactants and producing thin films of electro-optically active transition metal oxides.

  10. Synthesis and structural, magnetic, thermal, and transport properties of several transition metal oxides and aresnides

    SciTech Connect (OSTI)

    Das, Supriyo

    2010-05-16

    Oxide compounds containing the transition metal vanadium (V) have attracted a lot of attention in the field of condensed matter physics owing to their exhibition of interesting properties including metal-insulator transitons, structural transitions, ferromagnetic and antiferromagnetic orderings, and heavy fermion behavior. Binary vanadium oxides V{sub n}O{sub 2n-1} where 2 {le} n {le} 9 have triclinic structures and exhibit metal-insulator and antiferromagnetic transitions. The only exception is V{sub 7}O{sub 13} which remains metallic down to 4 K. The ternary vanadium oxide LiV{sub 2}O{sub 4} has the normal spinel structure, is metallic, does not undergo magnetic ordering and exhibits heavy fermion behavior below 10 K. CaV{sub 2}O{sub 4} has an orthorhombic structure with the vanadium spins forming zigzag chains and has been suggested to be a model system to study the gapless chiral phase. These provide great motivation for further investigation of some known vanadium compounds as well as to explore new vanadium compounds in search of new physics. This thesis consists, in part, of experimental studies involving sample preparation and magnetic, transport, thermal, and x-ray measurements on some strongly correlated eletron systems containing the transition metal vanadium. The compounds studied are LiV{sub 2}O{sub 4}, YV{sub 4}O{sub 8}, and YbV{sub 4}O{sub 8}. The recent discovery of superconductivity in RFeAsO{sub 1-x}F{sub x} (R = La, Ce, Pr, Gd, Tb, Dy, Sm, and Nd), and AFe{sub 2}As{sub 2} (A = Ba, Sr, Ca, and Eu) doped with K, Na, or Cs at the A site with relatively high T{sub c} has sparked tremendous activities in the condensed matter physics community and a renewed interest in the area of superconductivity as occurred following the discovery of the layered cuprate high T{sub c} superconductors in 1986. To discover more superconductors with hopefully higher T{sub c}'s, it is extremely important to investigate compounds having crystal structures related to the compounds showing high T{sub c} superconductivity. Along with the vanadium oxide compounds described before, this thesis describes our investigations of magnetic, structural, thermal and transport properties of EuPd{sub 2}Sb{sub 2} single crystals which have a crystal structure closely related to the AFe{sub 2}As{sub 2} compounds and also a study of the reaction kinetics of the formation of LaFeAsO{sub 1-x}F{sub x}.

  11. Hydrocracking and hydroisomerization of long-chain alkanes and polyolefins over metal-promoted anion-modified transition metal oxides

    DOE Patents [OSTI]

    Venkatesh, Koppampatti R. (Pittsburgh, PA); Hu, Jianli (Cranbury, NJ); Tierney, John W. (Pittsburgh, PA); Wender, Irving (Pittsburgh, PA)

    2001-01-01

    A method of cracking a feedstock by contacting the feedstock with a metal-promoted anion-modified metal oxide catalyst in the presence of hydrogen gas. The metal oxide of the catalyst is one or more of ZrO.sub.2, HfO.sub.2, TiO.sub.2 and SnO.sub.2, and the feedstock is principally chains of at least 20 carbon atoms. The metal-promoted anion-modified metal oxide catalyst contains one or more of Pt, Ni, Pd, Rh, Ir, Ru, (Mn & Fe) or mixtures of them present between about 0.2% to about 15% by weight of the catalyst. The metal-promoted anion-modified metal oxide catalyst contains one or more of SO.sub.4, WO.sub.3, or mixtures of them present between about 0.5% to about 20% by weight of the catalyst.

  12. Method of synthesizing a plurality of reactants and producing thin films of electro-optically active transition metal oxides

    DOE Patents [OSTI]

    Tracy, C. Edwin (Golden, CO); Benson, David K. (Golden, CO); Ruth, Marta R. (Golden, CO)

    1987-01-01

    A method of synthesizing electro-optically active reaction products from a plurality of reactants by inducing a reaction by plasma deposition among the reactants. The plasma reaction is effective for consolidating the reactants and producing thin films of electro-optically active transition metal oxides.

  13. New sol-gel synthetic route to transition and main-group metal oxide aerogels using inorganic salt precursors

    SciTech Connect (OSTI)

    Gash, A E; Tillotson, T M; Satcher Jr, J H; Hrubesh, L W; Simpson, R L

    2000-09-12

    We have developed a new sol-gel route to synthesize several transition and main-group metal oxide aerogels. The approach is straightforward, inexpensive, versatile, and it produces monolithic microporous materials with high surface areas. Specifically, we report the use of epoxides as gelation agents for the sol-gel synthesis of chromia aerogels and xerogels from simple Cr(III) inorganic salts. The dependence of both gel formation and its rate was studied by varying the solvent used, the Cr(III) precursor salt, the epoxide/Cr(III) ratio, as well as the type of epoxide employed. All of these variables were shown to affect the rate of gel formation and provide a convenient control of this parameter. Dried chromia aerogels were characterized by high-resolution transmission electron microscopy (HRTEM) and nitrogen adsorption/desorption analyses, results of which will be presented. Our studies have shown that rigid monolithic gels can be prepared from many different metal ions salts, provided the formal oxidation state of the metal ion is greater than or equal to +3. Conversely, when di-valent transition metal salts are used precipitated solids are the products.

  14. Transition metal sulfide loaded catalyst

    DOE Patents [OSTI]

    Maroni, Victor A. (Naperville, IL); Iton, Lennox E. (Downers Grove, IL); Pasterczyk, James W. (Westmont, IL); Winterer, Markus (Westmont, IL); Krause, Theodore R. (Lisle, IL)

    1994-01-01

    A zeolite based catalyst for activation and conversion of methane. A zeolite support includes a transition metal (Mo, Cr or W) sulfide disposed within the micropores of the zeolite. The catalyst allows activation and conversion of methane to C.sub.2 + hydrocarbons in a reducing atmosphere, thereby avoiding formation of oxides of carbon.

  15. Transition metal sulfide loaded catalyst

    DOE Patents [OSTI]

    Maroni, V.A.; Iton, L.E.; Pasterczyk, J.W.; Winterer, M.; Krause, T.R.

    1994-04-26

    A zeolite-based catalyst is described for activation and conversion of methane. A zeolite support includes a transition metal (Mo, Cr or W) sulfide disposed within the micropores of the zeolite. The catalyst allows activation and conversion of methane to C[sub 2]+ hydrocarbons in a reducing atmosphere, thereby avoiding formation of oxides of carbon.

  16. Oligocyclopentadienyl transition metal complexes

    SciTech Connect (OSTI)

    de Azevedo, Cristina G.; Vollhardt, K. Peter C.

    2002-01-18

    Synthesis, characterization, and reactivity studies of oligocyclopentadienyl transition metal complexes, namely those of fulvalene, tercyclopentadienyl, quatercyclopentadienyl, and pentacyclopentadienyl(cyclopentadienyl) are the subject of this account. Thermal-, photo-, and redox chemistries of homo- and heteropolynuclear complexes are described.

  17. Oxidative dehydrogenation (ODH) of ethane with O[subscript 2] as oxidant on selected transition metal-loaded zeolites

    SciTech Connect (OSTI)

    Lin, Xufeng; Hoel, Cathleen A.; Sachtler, Wolfgang M.H.; Poeppelmeier, Kenneth R.; Weitz, Eric

    2009-09-14

    Ni-, Cu-, and Fe-loaded acidic and basic Y zeolites were synthesized, and their catalytic properties for oxidative dehydrogenation of ethane (ODHE) to ethylene were characterized. Acidic Ni-loaded Y zeolite exhibits an ethylene productivity of up to 108 g{sub C{sub 2}H{sub 4}}g{sub cat}{sup -1} h{sup -1} with a selectivity of {approx}75%. Acidic Cu- and Fe-loaded Y zeolites have an ethylene productivity of up to 0.37 g{sub C{sub 2}H{sub 4}}g{sub cat}{sup -1} h{sup -1} and a selectivity of {approx}50%. For the same metal, the acidity of the zeolite favors both ODHE productivity and ethylene selectivity. Extended X-ray absorption fine structure (EXAFS) studies show that Ni, present in particles on Ni/HY during the ODHE catalytic process, contains both Ni-Ni and Ni-O bonds, and that the ratio of oxidized Ni versus metallic Ni increases with the temperature. The insights these studies provide into the ODHE reaction mechanism are discussed.

  18. Metal oxide films on metal

    DOE Patents [OSTI]

    Wu, Xin D. (Los Alamos, NM); Tiwari, Prabhat (Los Alamos, NM)

    1995-01-01

    A structure including a thin film of a conductive alkaline earth metal oxide selected from the group consisting of strontium ruthenium trioxide, calcium ruthenium trioxide, barium ruthenium trioxide, lanthanum-strontium cobalt oxide or mixed alkaline earth ruthenium trioxides thereof upon a thin film of a noble metal such as platinum is provided.

  19. Atomic-Resolution Visualization of Distinctive Chemical Mixing Behavior of Ni, Co and Mn with Li in Layered Lithium Transition-Metal Oxide Cathode Materials

    SciTech Connect (OSTI)

    Yan, Pengfei; Zheng, Jianming; Lv, Dongping; Wei, Yi; Zheng, Jiaxin; Wang, Zhiguo; Kuppan, Saravanan; Yu, Jianguo; Luo, Langli; Edwards, Danny J.; Olszta, Matthew J.; Amine, Khalil; Liu, Jun; Xiao, Jie; Pan, Feng; Chen, Guoying; Zhang, Jiguang; Wang, Chong M.

    2015-07-06

    Capacity and voltage fading of layer structured cathode based on lithium transition metal oxide is closely related to the lattice position and migration behavior of the transition metal ions. However, it is scarcely clear about the behavior of each of these transition metal ions. We report direct atomic resolution visualization of interatomic layer mixing of transition metal (Ni, Co, Mn) and lithium ions in layer structured oxide cathodes for lithium ion batteries. Using chemical imaging with aberration corrected scanning transmission electron microscope (STEM) and DFT calculations, we discovered that in the layered cathodes, Mn and Co tend to reside almost exclusively at the lattice site of transition metal (TM) layer in the structure or little interlayer mixing with Li. In contrast, Ni shows high degree of interlayer mixing with Li. The fraction of Ni ions reside in the Li layer followed a near linear dependence on total Ni concentration before reaching saturation. The observed distinctively different behavior of Ni with respect to Co and Mn provides new insights on both capacity and voltage fade in this class of cathode materials based on lithium and TM oxides, therefore providing scientific basis for selective tailoring of oxide cathode materials for enhanced performance.

  20. Transition Metal Switchable Mirror

    ScienceCinema (OSTI)

    None

    2013-05-29

    The switchable-mirrors technology was developed by Tom Richardson and Jonathan Slack of Berkeley Lab's Environmental Energy Technologies Division. By using transition metals rather than the rare earth metals used in the first metal-hydride switchable mirrors, Richardson and Slack were able to lower the cost and simplify the manufacturing process. Energy performance is improved as well, because the new windows can reflect or transmit both visible and infrared light. Besides windows for offices and homes, possible applications include automobile sunroofs, signs and displays, aircraft windows, and spacecraft. More information at: http://windows.lbl.gov/materials/chromogenics/default.htm

  1. Transition Metal Switchable Mirror

    ScienceCinema (OSTI)

    None

    2010-01-08

    The switchable-mirrors technology was developed by Tom Richardson and Jonathan Slack of Berkeley Lab's Environmental Energy Technologies Division. By using transition metals rather than the rare earth metals used in the first metal-hydride switchable mirrors, Richardson and Slack were able to lower the cost and simplify the manufacturing process. Energy performance is improved as well, because the new windows can reflect or transmit both visible and infrared light. Besides windows for offices and homes, possible applications include automobile sunroofs, signs and displays, aircraft windows, and spacecraft.

  2. Metal to semiconductor transition in metallic transition metal dichalcogenides

    SciTech Connect (OSTI)

    Li, Yan; Kang, Jun; Li, Jingbo; Tongay, Sefaattin; Wu, Junqiao; Yue, Qu

    2013-11-07

    We report on tuning the electronic and magnetic properties of metallic transition metal dichalcogenides (mTMDCs) by 2D to 1D size confinement. The stability of the mTMDC monolayers and nanoribbons is demonstrated by the larger binding energy compared to the experimentally available semiconducting TMDCs. The 2D MX{sub 2} (M?=?Nb, Ta; X?=?S, Se) monolayers are non-ferromagnetic metals and mechanically softer compared to their semiconducting TMDCs counterparts. Interestingly, mTMDCs undergo metal-to-semiconductor transition when the ribbon width approaches to ?13? and ?7? for zigzag and armchair edge terminations, respectively; then these ribbons convert back to metal when the ribbon widths further decrease. Zigzag terminated nanoribbons are ferromagnetic semiconductors, and their magnetic properties can also be tuned by hydrogen edge passivation, whereas the armchair nanoribbons are non-ferromagnetic semiconductors. Our results display that the mTMDCs offer a broad range of physical properties spanning from metallic to semiconducting and non-ferromagnetic to ferromagnetic that is ideal for applications where stable narrow bandgap semiconductors with different magnetic properties are desired.

  3. Method for dry etching of transition metals

    DOE Patents [OSTI]

    Ashby, C.I.H.; Baca, A.G.; Esherick, P.; Parmeter, J.E.; Rieger, D.J.; Shul, R.J.

    1998-09-29

    A method for dry etching of transition metals is disclosed. The method for dry etching of a transition metal (or a transition metal alloy such as a silicide) on a substrate comprises providing at least one nitrogen- or phosphorus-containing {pi}-acceptor ligand in proximity to the transition metal, and etching the transition metal to form a volatile transition metal/{pi}-acceptor ligand complex. The dry etching may be performed in a plasma etching system such as a reactive ion etching (RIE) system, a downstream plasma etching system (i.e. a plasma afterglow), a chemically-assisted ion beam etching (CAIBE) system or the like. The dry etching may also be performed by generating the {pi}-acceptor ligands directly from a ligand source gas (e.g. nitrosyl ligands generated from nitric oxide), or from contact with energized particles such as photons, electrons, ions, atoms, or molecules. In some preferred embodiments of the present invention, an intermediary reactant species such as carbonyl or a halide ligand is used for an initial chemical reaction with the transition metal, with the intermediary reactant species being replaced at least in part by the {pi}-acceptor ligand for forming the volatile transition metal/{pi}-acceptor ligand complex.

  4. Method for dry etching of transition metals

    DOE Patents [OSTI]

    Ashby, Carol I. H. (Edgewood, NM); Baca, Albert G. (Albuquerque, NM); Esherick, Peter (Albuquerque, NM); Parmeter, John E. (Albuquerque, NM); Rieger, Dennis J. (Tijeras, NM); Shul, Randy J. (Albuquerque, NM)

    1998-01-01

    A method for dry etching of transition metals. The method for dry etching of a transition metal (or a transition metal alloy such as a silicide) on a substrate comprises providing at least one nitrogen- or phosphorous-containing .pi.-acceptor ligand in proximity to the transition metal, and etching the transition metal to form a volatile transition metal/.pi.-acceptor ligand complex. The dry etching may be performed in a plasma etching system such as a reactive ion etching (RIE) system, a downstream plasma etching system (i.e. a plasma afterglow), a chemically-assisted ion beam etching (CAIBE) system or the like. The dry etching may also be performed by generating the .pi.-acceptor ligands directly from a ligand source gas (e.g. nitrosyl ligands generated from nitric oxide), or from contact with energized particles such as photons, electrons, ions, atoms, or molecules. In some preferred embodiments of the present invention, an intermediary reactant species such as carbonyl or a halide ligand is used for an initial chemical reaction with the transition metal, with the intermediary reactant species being replaced at least in part by the .pi.-acceptor ligand for forming the volatile transition metal/.pi.-acceptor ligand complex.

  5. STUDY MAGNETIC EXCITATIONS IN DOPED TRANSITION METAL OXIDES USING INELASTIC NEUTRON SCATTERING

    SciTech Connect (OSTI)

    Dai, Pengcheng

    2014-02-18

    Understanding the interplay between magnetism and superconductivity continues to be a hot topic in modern condensed matter physics. The discovery of high-temperature superconductivity in iron-based materials in 2008 provided an unique opportunity to compare and contrast these materials with traditional high-Tc copper oxide superconductors. Neutron scattering plays an important role in determining the dynamical spin properties in these materials. This proposal is a continuation of previous DOE supported proposal. This report summarizes the final progress we have made over from May 2005 till Aug. 2013. Overall, we continue to carry out extensive neutron scattering experiments on Fe-based materials, focusing on understanding their magnetic properties. In addition, we have established a materials laboratory at UT that has allowed us to grow these superconductors. Because neutron scattering typically demands a large amount of samples, by growing these materials in our own laboratory, we can now pursuit neutron scattering experiments over the entire electronic phase diagram, focusing on regions of interests. The material synthesis laboratory at UT was established entirely with the support of DOE funding. This not only allowed us to carry out neutron scattering experiments, but also permit us to provide samples to other US/International collaborators for studying these materials.

  6. Metal atom oxidation laser

    DOE Patents [OSTI]

    Jensen, R.J.; Rice, W.W.; Beattie, W.H.

    1975-10-28

    A chemical laser which operates by formation of metal or carbon atoms and reaction of such atoms with a gaseous oxidizer in an optical resonant cavity is described. The lasing species are diatomic or polyatomic in nature and are readily produced by exchange or other abstraction reactions between the metal or carbon atoms and the oxidizer. The lasing molecules may be metal or carbon monohalides or monoxides. (auth)

  7. Metal atom oxidation laser

    DOE Patents [OSTI]

    Jensen, R.J.; Rice, W.W.; Beattie, W.H.

    1975-10-28

    A chemical laser which operates by formation of metal or carbon atoms and reaction of such atoms with a gaseous oxidizer in an optical resonant cavity is described. The lasing species are diatomic or polyatomic in nature and are readily produced by exchange or other abstraction reactions between the metal or carbon atoms and the oxidizer. The lasing molecules may be metal or carbon monohalides or monoxides.

  8. Extracting metals directly from metal oxides

    DOE Patents [OSTI]

    Wai, C.M.; Smart, N.G.; Phelps, C.

    1997-02-25

    A method of extracting metals directly from metal oxides by exposing the oxide to a supercritical fluid solvent containing a chelating agent is described. Preferably, the metal is an actinide or a lanthanide. More preferably, the metal is uranium, thorium or plutonium. The chelating agent forms chelates that are soluble in the supercritical fluid, thereby allowing direct removal of the metal from the metal oxide. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is selected from the group consisting of {beta}-diketones, halogenated {beta}-diketones, phosphinic acids, halogenated phosphinic acids, carboxylic acids, halogenated carboxylic acids, and mixtures thereof. In especially preferred embodiments, at least one of the chelating agents is fluorinated. The method provides an environmentally benign process for removing metals from metal oxides without using acids or biologically harmful solvents. The chelate and supercritical fluid can be regenerated, and the metal recovered, to provide an economic, efficient process. 4 figs.

  9. Extracting metals directly from metal oxides

    DOE Patents [OSTI]

    Wai, Chien M.; Smart, Neil G.; Phelps, Cindy

    1997-01-01

    A method of extracting metals directly from metal oxides by exposing the oxide to a supercritical fluid solvent containing a chelating agent is described. Preferably, the metal is an actinide or a lanthanide. More preferably, the metal is uranium, thorium or plutonium. The chelating agent forms chelates that are soluble in the supercritical fluid, thereby allowing direct removal of the metal from the metal oxide. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is selected from the group consisting of .beta.-diketones, halogenated .beta.-diketones, phosphinic acids, halogenated phosphinic acids, carboxylic acids, halogenated carboxylic acids, and mixtures thereof. In especially preferred embodiments, at least one of the chelating agents is fluorinated. The method provides an environmentally benign process for removing metals from metal oxides without using acids or biologically harmful solvents. The chelate and supercritical fluid can be regenerated, and the metal recovered, to provide an economic, efficient process.

  10. Lithium metal oxide electrodes for lithium batteries

    DOE Patents [OSTI]

    Thackeray, Michael M. (Naperville, IL); Kim, Jeom-Soo (Naperville, IL); Johnson, Christopher S. (Naperville, IL)

    2008-01-01

    An uncycled electrode for a non-aqueous lithium electrochemical cell including a lithium metal oxide having the formula Li.sub.(2+2x)/(2+x)M'.sub.2x/(2+x)M.sub.(2-2x)/(2+x)O.sub.2-.delta., in which 0.ltoreq.x<1 and .delta. is less than 0.2, and in which M is a non-lithium metal ion with an average trivalent oxidation state selected from two or more of the first row transition metals or lighter metal elements in the periodic table, and M' is one or more ions with an average tetravalent oxidation state selected from the first and second row transition metal elements and Sn. Methods of preconditioning the electrodes are disclosed as are electrochemical cells and batteries containing the electrodes.

  11. Lithium metal oxide electrodes for lithium batteries

    DOE Patents [OSTI]

    Thackeray, Michael M.; Johnson, Christopher S.; Amine, Khalil; Kang, Sun-Ho

    2010-06-08

    An uncycled preconditioned electrode for a non-aqueous lithium electrochemical cell including a lithium metal oxide having the formula xLi.sub.2-yH.sub.yO.xM'O.sub.2.(1-x)Li.sub.1-zH.sub.zMO.sub.2 in which 0metal ion with an average trivalent oxidation state selected from two or more of the first row transition metals or lighter metal elements in the periodic table, and M' is one or more ions with an average tetravalent oxidation state selected from the first and second row transition metal elements and Sn. The xLi.sub.2-yH.sub.y.xM'O.sub.2.(1-x)Li.sub.1-zH.sub.zMO.sub.2 material is prepared by preconditioning a precursor lithium metal oxide (i.e., xLi.sub.2M'O.sub.3.(1-x)LiMO.sub.2) with a proton-containing medium with a pH<7.0 containing an inorganic acid. Methods of preparing the electrodes are disclosed, as are electrochemical cells and batteries containing the electrodes.

  12. Time-Resolved XAFS Spectroscopic Studies of B-H and N-H Oxidative Addition to Transition Metal Catalysts Relevant to Hydrogen Storage

    SciTech Connect (OSTI)

    Bitterwolf, Thomas E.

    2014-12-09

    Successful catalytic dehydrogenation of aminoborane, H3NBH3, prompted questions as to the potential role of N-H oxidative addition in the mechanisms of these processes. N-H oxidative addition reactions are rare, and in all cases appear to involve initial dative bonding to the metal by the amine lone pairs followed by transfer of a proton to the basic metal. Aminoborane and its trimethylborane derivative block this mechanism and, in principle, should permit authentic N-H oxidative attrition to occur. Extensive experimental work failed to confirm this hypothesis. In all cases either B-H complexation or oxidative addition of solvent C-H bonds dominate the chemistry.

  13. Process for making transition metal nitride whiskers

    DOE Patents [OSTI]

    Bamberger, Carlos E. (Oak Ridge, TN)

    1989-01-01

    A process for making metal nitrides, particularly titanium nitride whiskers, using a cyanide salt as a reducing agent for a metal compound in the presence of an alkali metal oxide. Sodium cyanide, various titanates and titanium oxide mixed with sodium oxide react to provide titanium nitride whiskers that can be used as reinforcement to ceramic composites.

  14. Process for making transition metal nitride whiskers

    DOE Patents [OSTI]

    Bamberger, C.E.

    1988-04-12

    A process for making metal nitrides, particularly titanium nitride whiskers, using a cyanide salt as a reducing agent for a metal compound in the presence of an alkali metal oxide. Sodium cyanide, various titanates and titanium oxide mixed with sodium oxide react to provide titanium nitride whiskers that can be used as reinforcement to ceramic composites. 1 fig., 1 tab.

  15. Synthesis of transition metal carbonitrides

    DOE Patents [OSTI]

    Munir, Zuhair A. R. (Davis, CA); Eslamloo-Grami, Maryam (Davis, CA)

    1994-01-01

    Transition metal carbonitrides (in particular, titanium carbonitride, TiC.sub.0.5 N.sub.0.5) are synthesized by a self-propagating reaction between the metal (e.g., titanium) and carbon in a nitrogen atmosphere. Complete conversion to the carbonitride phase is achieved with the addition of TiN as diluent and with a nitrogen pressure .gtoreq.0.6 MPa. Thermodynamic phase-stability calculations and experimental characterizations of quenched samples provided revealed that the mechanism of formation of the carbonitride is a two-step process. The first step involves the formation of the nonstoichiometric carbide, TiC.sub.0.5, and is followed by the formation of the product by the incorporation of nitrogen in the defect-structure carbide.

  16. Strategies to curb structural changes of lithium/transition metal oxide cathode materials & the changes' effects on thermal & cycling stability

    SciTech Connect (OSTI)

    Yu, Xiqian; Hu, Enyuan; Bak, Seongmin; Zhou, Yong -Ning; Yang, Xiao -Qing

    2015-12-07

    Structural transformation behaviors of several typical oxide cathode materials during a heating process are reviewed in detail to provide in-depth understanding of the key factors governing the thermal stability of these materials. Furthermore, we also discuss applying the information about heat induced structural evolution in the study of electrochemically induced structural changes. All these discussions are expected to provide valuable insights for designing oxide cathode materials with significantly improved structural stability for safe, long-life lithium ion batteries, as the safety of lithium-ion batteries is a critical issue. As a result, it is widely accepted that the thermal instability of the cathodes is one of the most critical factors in thermal runaway and related safety problems.

  17. Strategies to curb structural changes of lithium/transition metal oxide cathode materials & the changes' effects on thermal & cycling stability

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Yu, Xiqian; Hu, Enyuan; Bak, Seongmin; Zhou, Yong -Ning; Yang, Xiao -Qing

    2015-12-07

    Structural transformation behaviors of several typical oxide cathode materials during a heating process are reviewed in detail to provide in-depth understanding of the key factors governing the thermal stability of these materials. Furthermore, we also discuss applying the information about heat induced structural evolution in the study of electrochemically induced structural changes. All these discussions are expected to provide valuable insights for designing oxide cathode materials with significantly improved structural stability for safe, long-life lithium ion batteries, as the safety of lithium-ion batteries is a critical issue. As a result, it is widely accepted that the thermal instability of themore » cathodes is one of the most critical factors in thermal runaway and related safety problems.« less

  18. Strategies to curb structural changes of lithium/transition metal oxide cathode materials & the changes' effects on thermal & cycling stability

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Yu, Xiqian; Hu, Enyuan; Bak, Seongmin; Zhou, Yong -Ning; Yang, Xiao -Qing

    2015-12-07

    Structural transformation behaviors of several typical oxide cathode materials during a heating process are reviewed in detail to provide in-depth understanding of the key factors governing the thermal stability of these materials. Furthermore, we also discuss applying the information about heat induced structural evolution in the study of electrochemically induced structural changes. All these discussions are expected to provide valuable insights for designing oxide cathode materials with significantly improved structural stability for safe, long-life lithium ion batteries, as the safety of lithium-ion batteries is a critical issue. As a result, it is widely accepted that the thermal instability of themore »cathodes is one of the most critical factors in thermal runaway and related safety problems.« less

  19. Accurate Band-Structure Calculations for the 3d Transition Metal...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    developed a method to calculate accurate band structures and bandgap energies for 3d transition metal oxides using an augmented GW formalism. Significance and Impact This approach...

  20. Thin film hydrous metal oxide catalysts

    DOE Patents [OSTI]

    Dosch, Robert G. (Albuquerque, NM); Stephens, Howard P. (Albuquerque, NM)

    1995-01-01

    Thin film (<100 nm) hydrous metal oxide catalysts are prepared by 1) synthesis of a hydrous metal oxide, 2) deposition of the hydrous metal oxide upon an inert support surface, 3) ion exchange with catalytically active metals, and 4) activating the hydrous metal oxide catalysts.

  1. Nanostructured Metal Oxide Anodes (Presentation)

    SciTech Connect (OSTI)

    Dillon, A. C.; Riley, L. A.; Lee, S.-H.; Kim, Y.-H.; Ban, C.; Gillaspie, D. T.; Pesaran, A.

    2009-05-01

    This summarizes NREL's FY09 battery materials research activity in developing metal oxide nanostructured anodes to enable high-energy, durable and affordable li-ion batteries for HEVs and PHEVs.

  2. METAL OXIDE NANOPARTICLES

    SciTech Connect (OSTI)

    FERNANDEZ-GARCIA,M.; RODGRIGUEZ, J.A.

    2007-10-01

    This chapter covers the fundamental science, synthesis, characterization, physicochemical properties and applications of oxide nanomaterials. Explains fundamental aspects that determine the growth and behavior of these systems, briefly examines synthetic procedures using bottom-up and top-down fabrication technologies, discusses the sophisticated experimental techniques and state of the art theory results used to characterize the physico-chemical properties of oxide solids and describe the current knowledge concerning key oxide materials with important technological applications.

  3. Metal oxide nanostructures with hierarchical morphology

    DOE Patents [OSTI]

    Ren, Zhifeng (Newton, MA); Lao, Jing Yu (Saline, MI); Banerjee, Debasish (Ann Arbor, MI)

    2007-11-13

    The present invention relates generally to metal oxide materials with varied symmetrical nanostructure morphologies. In particular, the present invention provides metal oxide materials comprising one or more metallic oxides with three-dimensionally ordered nanostructural morphologies, including hierarchical morphologies. The present invention also provides methods for producing such metal oxide materials.

  4. Metal oxide porous ceramic membranes with small pore sizes

    DOE Patents [OSTI]

    Anderson, Marc A. (Madison, WI); Xu, Qunyin (Madison, WI)

    1992-01-01

    A method is disclosed for the production of metal oxide ceramic membranes of very small pore size. The process is particularly useful in the creation of titanium and other transition metal oxide membranes. The method utilizes a sol-gel process in which the rate of particle formation is controlled by substituting a relatively large alcohol in the metal alkoxide and by limiting the available water. Stable, transparent metal oxide ceramic membranes are created having a narrow distribution of pore size, with the pore diameter being manipulable in the range of 5 to 40 Angstroms.

  5. Metal oxide porous ceramic membranes with small pore sizes

    DOE Patents [OSTI]

    Anderson, Marc A. (Madison, WI); Xu, Qunyin (Madison, WI)

    1991-01-01

    A method is disclosed for the production of metal oxide ceramic membranes of very small pore size. The process is particularly useful in the creation of titanium and other transition metal oxide membranes. The method utilizes a sol-gel process in which the rate of particle formation is controlled by substituting a relatively large alcohol in the metal alkoxide and by limiting the available water. Stable, transparent metal oxide ceramic membranes are created having a narrow distribution of pore size, with the pore diameter being manipulable in the range of 5 to 40 Angstroms.

  6. Lithium metal reduction of plutonium oxide to produce plutonium metal

    DOE Patents [OSTI]

    Coops, Melvin S. (Livermore, CA)

    1992-01-01

    A method is described for the chemical reduction of plutonium oxides to plutonium metal by the use of pure lithium metal. Lithium metal is used to reduce plutonium oxide to alpha plutonium metal (alpha-Pu). The lithium oxide by-product is reclaimed by sublimation and converted to the chloride salt, and after electrolysis, is removed as lithium metal. Zinc may be used as a solvent metal to improve thermodynamics of the reduction reaction at lower temperatures. Lithium metal reduction enables plutonium oxide reduction without the production of huge quantities of CaO--CaCl.sub.2 residues normally produced in conventional direct oxide reduction processes.

  7. Synthesis of Metal-Metal Oxide Catalysts and Electrocatalysts...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Synthesis of Metal-Metal Oxide Catalysts and Electrocatalysts Brookhaven National Laboratory Contact BNL About This Technology Publications: PDF Document Publication...

  8. Method for plating with metal oxides

    DOE Patents [OSTI]

    Silver, Gary L. (Centerville, OH); Martin, Frank S. (Farmersville, OH)

    1994-08-23

    A method of plating hydrous metal oxides on at least one substrate, which method is indifferent to the electrochemical properties of the substrate, and comprises reacting metallic ions in aqueous solution with an appropriate oxidizing agent such as sodium hypochlorite or calcium sulfite with oxygen under suitable conditions of pH and concentration such that oxidation and precipitation of metal oxide are sufficiently slow to allow satisfactory plating of metal oxide on the substrate.

  9. Method for plating with metal oxides

    DOE Patents [OSTI]

    Silver, G.L.; Martin, F.S.

    1994-08-23

    A method is disclosed of plating hydrous metal oxides on at least one substrate, which method is indifferent to the electrochemical properties of the substrate, and comprises reacting metallic ions in aqueous solution with an appropriate oxidizing agent such as sodium hypochlorite or calcium sulfite with oxygen under suitable conditions of pH and concentration such that oxidation and precipitation of metal oxide are sufficiently slow to allow satisfactory plating of metal oxide on the substrate. 1 fig.

  10. Preparation of uniform nanoparticles of ultra-high purity metal oxides, mixed metal oxides, metals, and metal alloys

    DOE Patents [OSTI]

    Woodfield, Brian F.; Liu, Shengfeng; Boerio-Goates, Juliana; Liu, Qingyuan; Smith, Stacey Janel

    2012-07-03

    In preferred embodiments, metal nanoparticles, mixed-metal (alloy) nanoparticles, metal oxide nanoparticles and mixed-metal oxide nanoparticles are provided. According to embodiments, the nanoparticles may possess narrow size distributions and high purities. In certain preferred embodiments, methods of preparing metal nanoparticles, mixed-metal nanoparticles, metal oxide nanoparticles and mixed-metal nanoparticles are provided. These methods may provide tight control of particle size, size distribution, and oxidation state. Other preferred embodiments relate to a precursor material that may be used to form nanoparticles. In addition, products prepared from such nanoparticles are disclosed.

  11. Memristor using a transition metal nitride insulator (Patent...

    Office of Scientific and Technical Information (OSTI)

    Patent: Memristor using a transition metal nitride insulator Citation Details In-Document Search Title: Memristor using a transition metal nitride insulator You are accessing a...

  12. Graphene physics and insulator-metal transition in compressed...

    Office of Scientific and Technical Information (OSTI)

    Graphene physics and insulator-metal transition in compressed hydrogen Title: Graphene physics and insulator-metal transition in compressed hydrogen Authors: Naumov, Ivan I. ; ...

  13. Proximity-induced magnetism in transition-metal substituted graphene...

    Office of Scientific and Technical Information (OSTI)

    Proximity-induced magnetism in transition-metal substituted graphene Citation Details In-Document Search Title: Proximity-induced magnetism in transition-metal substituted graphene ...

  14. Project Profile: High Performance Reduction/Oxidation Metal Oxides for

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Thermochemical Energy Storage | Department of Energy Project Profile: High Performance Reduction/Oxidation Metal Oxides for Thermochemical Energy Storage Project Profile: High Performance Reduction/Oxidation Metal Oxides for Thermochemical Energy Storage Sandia National Laboratory Logo Sandia National Lab (Sandia), through the Concentrating Solar Power: Efficiently Leveraging Equilibrium Mechanisms for Engineering New Thermochemical Storage (CSP: ELEMENTS) funding program, is systematically

  15. Method of boronizing transition metal surfaces

    DOE Patents [OSTI]

    Koyama, Koichiro (Hyogo, JP); Shimotake, Hiroshi (Hinsdale, IL)

    1983-01-01

    A method is presented for preparing a boride layer on a transition metal substrate for use in corrosive environments or as a harden surface in machine applications. This method is particularly useful in treating current collectors for use within a high temperature and corrosive electrochemical cell environment. A melt of a alkali metal boride tetrafluoride salt including such as KF to lower its melting point is prepared including a dissolved boron containing material, for instance NiB, MnB.sub.2, or CrB.sub.2. A transition metal to be coated is immersed in the melt at a temperature of no more than 700.degree. C. and a surface boride layer of that transition metal is formed within a period of about 24 hours on the substrate surface.

  16. Method of boronizing transition metal surfaces

    DOE Patents [OSTI]

    Koyama, Koichiro; Shimotake, Hiroshi.

    1983-08-16

    A method is presented for preparing a boride layer on a transition metal substrate for use in corrosive environments or as a harden surface in machine applications. This method is particularly useful in treating current collectors for use within a high temperature and corrosive electrochemical cell environment. A melt of a alkali metal boride tetrafluoride salt including such as KF to lower its melting point is prepared including a dissolved boron containing material, for instance NiB, MnB[sub 2], or CrB[sub 2]. A transition metal to be coated is immersed in the melt at a temperature of no more than 700 C and a surface boride layer of that transition metal is formed within a period of about 24 hours on the substrate surface. 4 figs.

  17. Microwave-assisted synthesis of transition metal phosphide

    DOE Patents [OSTI]

    Viswanathan, Tito

    2014-12-30

    A method of synthesizing transition metal phosphide. In one embodiment, the method has the steps of preparing a transition metal lignosulfonate, mixing the transition metal lignosulfonate with phosphoric acid to form a mixture, and subjecting the mixture to a microwave radiation for a duration of time effective to obtain a transition metal phosphide.

  18. [Transition metal mediated transformations of small molecules

    SciTech Connect (OSTI)

    Sen, A.

    1992-01-01

    Work on organotransition metal chemistry, homogeneous and heterogeneous catalysis is summarized. Several cationic palladium(II) complexes with bulky phosphine or pyridine ligands were discovered that are highly selective catalysts for linear dimerization of vinyl monomers and linear polymerization of p-divinylbenzene, the reactions proceeding through a carbocationic mechanism. Our studies were continued on alternating olefin-carbon monoxide copolymers. The copolymerization reaction and reactivity of copolymers were examined. New catalytic systems for alternating copolymerization of [alpha]-olefins with CO were discovered. In the case of styrene derivatives, tactic copolymers were obtained. Poly(ethylenepyrrolediyl) derivatives were synthesized from alternating ethylene-carbon monoxide copolymer and become electronic conductors when doped with iodine. A catalytic system for direct synthesis of polyureas and polyoxamides from and diamines was also discovered. Pt metal catalyzed the oxidation of ethers, esters, and amines to carboxylic acids and the oxidation of olefins to 1,2-diols. Anaerobic and aerobic decomposition of molybdenum(VI)-oxoalkyl compounds were studied for heterogeneous oxidation of alkanes and olefins on Mo(VI)-oxide surfaces. Synthesis of polymer-trapped metal, metal oxide, and metal sulfide nanoclusters (size <1--10 nm) was studied.

  19. Ammonia release method for depositing metal oxides

    DOE Patents [OSTI]

    Silver, Gary L. (Centerville, OH); Martin, Frank S. (Farmersville, OH)

    1994-12-13

    A method of depositing metal oxides on substrates which is indifferent to the electrochemical properties of the substrates and which comprises forming ammine complexes containing metal ions and thereafter effecting removal of ammonia from the ammine complexes so as to permit slow precipitation and deposition of metal oxide on the substrates.

  20. Ammonia release method for depositing metal oxides

    DOE Patents [OSTI]

    Silver, G.L.; Martin, F.S.

    1994-12-13

    A method is described for depositing metal oxides on substrates which is indifferent to the electrochemical properties of the substrates and which comprises forming ammine complexes containing metal ions and thereafter effecting removal of ammonia from the ammine complexes so as to permit slow precipitation and deposition of metal oxide on the substrates. 1 figure.

  1. Method for producing metal oxide nanoparticles

    DOE Patents [OSTI]

    Phillips, Jonathan (Santa Fe, NM); Mendoza, Daniel (Santa Fe, NM); Chen, Chun-Ku (Albuquerque, NM)

    2008-04-15

    Method for producing metal oxide nanoparticles. The method includes generating an aerosol of solid metallic microparticles, generating plasma with a plasma hot zone at a temperature sufficiently high to vaporize the microparticles into metal vapor, and directing the aerosol into the hot zone of the plasma. The microparticles vaporize in the hot zone into metal vapor. The metal vapor is directed away from the hot zone and into the cooler plasma afterglow where it oxidizes, cools and condenses to form solid metal oxide nanoparticles.

  2. Metal oxide composite dosimeter method and material

    DOE Patents [OSTI]

    Miller, Steven D. (Richland, WA)

    1998-01-01

    The present invention is a method of measuring a radiation dose wherein a radiation responsive material consisting essentially of metal oxide is first exposed to ionizing radiation. The metal oxide is then stimulating with light thereby causing the radiation responsive material to photoluminesce. Photons emitted from the metal oxide as a result of photoluminescence may be counted to provide a measure of the ionizing radiation.

  3. Metal complexes of substituted Gable porphyrins as oxidation catalysts

    DOE Patents [OSTI]

    Lyons, J.E.; Ellis, P.E. Jr.; Wagner, R.W.

    1996-01-02

    Transition metal complexes of Gable porphyrins are disclosed having two porphyrin rings connected through a linking group, and having on the porphyrin rings electron-withdrawing groups, such as halogen, nitro or cyano. These complexes are useful as catalysts for the oxidation of organic compounds, e.g. alkanes.

  4. Metal complexes of substituted Gable porphyrins as oxidation catalysts

    DOE Patents [OSTI]

    Lyons, James E.; Ellis, Jr., Paul E.; Wagner, Richard W.

    1996-01-01

    Transition metal complexes of Gable porphyrins having two porphyrin rings connected through a linking group, and having on the porphyrin rings electron-withdrawing groups, such as halogen, nitro or cyano. These complexes are useful as catalysts for the oxidation of organic compounds, e.g. alkanes.

  5. Reduction of Metal Oxide to Metal using Ionic Liquids

    SciTech Connect (OSTI)

    Dr. Ramana Reddy

    2012-04-12

    A novel pathway for the high efficiency production of metal from metal oxide means of electrolysis in ionic liquids at low temperature was investigated. The main emphasis was to eliminate the use of carbon and high temperature application in the reduction of metal oxides to metals. The emphasis of this research was to produce metals such as Zn, and Pb that are normally produced by the application of very high temperatures. The reduction of zinc oxide to zinc and lead oxide to lead were investigated. This study involved three steps in accomplishing the final goal of reduction of metal oxide to metal using ionic liquids: 1) Dissolution of metal oxide in an ionic liquid, 2) Determination of reduction potential using cyclic voltammetry (CV) and 3) Reduction of the dissolved metal oxide. Ionic liquids provide additional advantage by offering a wide potential range for the deposition. In each and every step of the process, more than one process variable has been examined. Experimental results for electrochemical extraction of Zn from ZnO and Pb from PbO using eutectic mixtures of Urea ((NH2)2CO) and Choline chloride (HOC2H4N(CH3)3+Cl-) or (ChCl) in a molar ratio 2:1, varying voltage and temperatures were carried out. Fourier Transform Infra-Red (FTIR) spectroscopy studies of ionic liquids with and without metal oxide additions were conducted. FTIR and induction coupled plasma spectroscopy (ICPS) was used in the characterization of the metal oxide dissolved ionic liquid. Electrochemical experiments were conducted using EG&G potentiostat/galvanostat with three electrode cell systems. Cyclic voltammetry was used in the determination of reduction potentials for the deposition of metals. Chronoamperometric experiments were carried out in the potential range of -0.6V to -1.9V for lead and -1.4V to -1.9V for zinc. The deposits were characterized using XRD and SEM-EDS for phase, morphological and elemental analysis. The results showed that pure metal was deposited on the cathode. Successful extraction of metal from metal oxide dissolved in Urea/ChCl (2:1) was accomplished. The current efficiencies were relatively high in both the metal deposition processes with current efficiency greater than 86% for lead and 95% for zinc. This technology will advance the metal oxide reduction process by increasing the process efficiency and also eliminate the production of CO2 which makes this an environmentally benign technology for metal extraction.

  6. Transition metals on the (0001) surface of graphite: Fundamental...

    Office of Scientific and Technical Information (OSTI)

    metals on the (0001) surface of graphite: Fundamental aspects of adsorption, diffusion, and morphology Citation Details In-Document Search Title: Transition metals on the...

  7. Tuning of the Metal-Insulator Transition via Alkali Adsorption

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Tuning of the Metal-Insulator Transition via Alkali Adsorption Tuning of the Metal-Insulator Transition via Alkali Adsorption Print Wednesday, 29 March 2006 00:00 Turning a...

  8. Nanocomposite of graphene and metal oxide materials

    DOE Patents [OSTI]

    Liu, Jun; Aksay, Ilhan A.; Choi, Daiwon; Wang, Donghai; Yang, Zhenguo

    2013-10-15

    Nanocomposite materials comprising a metal oxide bonded to at least one graphene material. The nanocomposite materials exhibit a specific capacity of at least twice that of the metal oxide material without the graphene at a charge/discharge rate greater than about 10 C.

  9. Nanocomposite of graphene and metal oxide materials

    DOE Patents [OSTI]

    Liu, Jun; Aksay, Ilhan A.; Choi, Daiwon; Wang, Donghai; Yang, Zhenguo

    2012-09-04

    Nanocomposite materials comprising a metal oxide bonded to at least one graphene material. The nanocomposite materials exhibit a specific capacity of at least twice that of the metal oxide material without the graphene at a charge/discharge rate greater than about 10C.

  10. Nanocomposite of graphene and metal oxide materials

    DOE Patents [OSTI]

    Liu, Jun; Aksay, Ilhan A.; Choi, Daiwon; Wang, Donghai; Yang, Zhenguo

    2015-06-30

    Nanocomposite materials comprising a metal oxide bonded to at least one graphene material. The nanocomposite materials exhibit a specific capacity of at least twice that of the metal oxide material without the graphene at a charge/discharge rate greater than about 10 C.

  11. Spin transition in a four-coordinate iron oxide

    SciTech Connect (OSTI)

    Kawakami, T. [Nihon University, Tokyo; Sutou, S. [Nihon University, Tokyo; Hirama, H. [Nihon University, Tokyo; Sekiya, Y. [Nihon University, Tokyo; Makino, T. [Nihon University, Tokyo; Tsujimoto, Y. [Kyoto University, Japan; Kitada, A. [Kyoto University, Japan; Tassel, C. [Kyoto University, Japan; Kageyama, H. [Kyoto University, Japan; Yoshimura, K. [Kyoto University, Japan; Chen, Xingqiu [ORNL; Fu, Chong Long [ORNL; Okada, T. [University of Tokyo, Tokyo, Japan; Yagi, T. [University of Tokyo, Tokyo, Japan; Hayashi, N. [Kyoto University, Japan; Nasu, S. [Osaka University; Podloucky, R. [Institut fur Physikalische Chemie der RWTH; Takano, M. [Kyoto University, Japan

    2009-01-01

    The spin transition, or spin crossover, is a manifestation of electronic instability induced by external constraints such as pressure1. Among known examples that exhibit spin transition, 3d ions with d6 electron configurations represent the vast majority, but the spin transition observed thus far has been almost exclusively limited to that between high-spin (S = 2) and low-spin (S = 0) states2-9. Here we report a novel high-spin to intermediate-spin (S = 1) state transition at 33 GPa induced by pressurization of an antiferromagnetic insulator SrFeO2 with a square planar coordination10. The change in spin multiplicity brings to ferromagnetism as well as metallicity, yet keeping the ordering temperature far above ambient. First-principles calculations attribute the origin of the transition to the strong inlayer hybridization between Fe dx 2 -y 2 O p , leading to a pressure-induced electronic instability toward the depopulation of Fe dx 2 -y 2 O p antibonding states. Furthermore, the ferromagnetic S = 1 state is half-metallic due to the inception of half-occupied spin-down (dxz, dyz) degenerate states upon spin transition. These results highlight the square-planar coordinated iron oxides as a new class of magnetic and electric materials and provide new avenues toward realizing multi-functional sensors and data-storage devices.

  12. Method of producing adherent metal oxide coatings on metallic surfaces

    DOE Patents [OSTI]

    Lane, Michael H. (Clifton Park, NY); Varrin, Jr., Robert D. (McLean, VA)

    2001-01-01

    Provided is a process of producing an adherent synthetic corrosion product (sludge) coating on metallic surfaces. The method involves a chemical reaction between a dry solid powder mixture of at least one reactive metal oxide with orthophosphoric acid to produce a coating in which the particles are bound together and the matrix is adherent to the metallic surface.

  13. Redox chemistry and metal-insulator transitions intertwined | Center for

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Gas SeparationsRelevant to Clean Energy Technologies | Blandine Jerome Redox chemistry and metal-insulator transitions intertwined

  14. Single-layer transition metal sulfide catalysts

    DOE Patents [OSTI]

    Thoma, Steven G. (Albuquerque, NM)

    2011-05-31

    Transition Metal Sulfides (TMS), such as molybdenum disulfide (MoS.sub.2), are the petroleum industry's "workhorse" catalysts for upgrading heavy petroleum feedstocks and removing sulfur, nitrogen and other pollutants from fuels. We have developed an improved synthesis technique to produce SLTMS catalysts, such as molybdenum disulfide, with potentially greater activity and specificity than those currently available. Applications for this technology include heavy feed upgrading, in-situ catalysis, bio-fuel conversion and coal liquefaction.

  15. Method for making monolithic metal oxide aerogels

    DOE Patents [OSTI]

    Droege, M.W.; Coronado, P.R.; Hair, L.M.

    1995-03-07

    Transparent, monolithic metal oxide aerogels of varying densities are produced using a method in which a metal alkoxide solution and a catalyst solution are prepared separately and reacted. The resulting hydrolyzed-condensed colloidal solution is gelled, and the wet gel is contained within a sealed, but gas permeable, containment vessel during supercritical extraction of the solvent. The present invention is especially advantageous for making metal oxides other than silica that are prone to forming opaque, cracked aerogels. 6 figs.

  16. Method for making monolithic metal oxide aerogels

    DOE Patents [OSTI]

    Droege, Michael W. (Livermore, CA); Coronado, Paul R. (Livermore, CA); Hair, Lucy M. (Livermore, CA)

    1995-01-01

    Transparent, monolithic metal oxide aerogels of varying densities are produced using a method in which a metal alkoxide solution and a catalyst solution are prepared separately and reacted. The resulting hydrolyzed-condensed colloidal solution is gelled, and the wet gel is contained within a sealed, but gas permeable, containment vessel during supercritical extraction of the solvent. The present invention is especially advantageous for making metal oxides other than silica that are prone to forming opaque, cracked aerogels.

  17. Three-Electrode Metal Oxide Reduction Cell

    DOE Patents [OSTI]

    Dees, Dennis W.; Ackerman, John P.

    2005-06-28

    A method of electrochemically reducing a metal oxide to the metal in an electrochemical cell is disclosed along with the cell. Each of the anode and cathode operate at their respective maximum reaction rates. An electrolyte and an anode at which oxygen can be evolved, and a cathode including a metal oxide to be reduced are included as is a third electrode with independent power supplies connecting the anode and the third electrode and the cathode and the third electrode.

  18. Three-electrode metal oxide reduction cell

    DOE Patents [OSTI]

    Dees, Dennis W.; Ackerman, John P.

    2008-08-12

    A method of electrochemically reducing a metal oxide to the metal in an electrochemical cell is disclosed along with the cell. Each of the anode and cathode operate at their respective maximum reaction rates. An electrolyte and an anode at which oxygen can be evolved, and a cathode including a metal oxide to be reduced are included as is a third electrode with independent power supplies connecting the anode and the third electrode and the cathode and the third electrode.

  19. Direct electrochemical reduction of metal-oxides

    DOE Patents [OSTI]

    Redey, Laszlo I.; Gourishankar, Karthick

    2003-01-01

    A method of controlling the direct electrolytic reduction of a metal oxide or mixtures of metal oxides to the corresponding metal or metals. A non-consumable anode and a cathode and a salt electrolyte with a first reference electrode near the non-consumable anode and a second reference electrode near the cathode are used. Oxygen gas is produced and removed from the cell. The anode potential is compared to the first reference electrode to prevent anode dissolution and gas evolution other than oxygen, and the cathode potential is compared to the second reference electrode to prevent production of reductant metal from ions in the electrolyte.

  20. Methods of producing adsorption media including a metal oxide

    DOE Patents [OSTI]

    Mann, Nicholas R; Tranter, Troy J

    2014-03-04

    Methods of producing a metal oxide are disclosed. The method comprises dissolving a metal salt in a reaction solvent to form a metal salt/reaction solvent solution. The metal salt is converted to a metal oxide and a caustic solution is added to the metal oxide/reaction solvent solution to adjust the pH of the metal oxide/reaction solvent solution to less than approximately 7.0. The metal oxide is precipitated and recovered. A method of producing adsorption media including the metal oxide is also disclosed, as is a precursor of an active component including particles of a metal oxide.

  1. Monolithic Metal Oxide based Composite Nanowire Lean NOx Emission...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Monolithic Metal Oxide based Composite Nanowire Lean NOx Emission Control Catalysts Monolithic Metal Oxide based Composite Nanowire Lean NOx Emission Control Catalysts Presents...

  2. Patent: Microbial-mediated method for metal oxide nanoparticle formation |

    Office of Scientific and Technical Information (OSTI)

    DOEpatents Microbial-mediated method for metal oxide nanoparticle formation Citation Details Title: Microbial-mediated method for metal oxide nanoparticle formation

  3. Catalytic production of metal carbonyls from metal oxides

    DOE Patents [OSTI]

    Sapienza, Richard S. (Shoreham, NY); Slegeir, William A. (Hampton Bays, NY); Foran, Michael T. (Rocky Point, NY)

    1984-01-01

    This invention relates to the formation of metal carbonyls from metal oxides and specially the formation of molybdenum carbonyl and iron carbonyl from their respective oxides. Copper is used here in admixed form or used in chemically combined form as copper molybdate. The copper/metal oxide combination or combined copper is utilized with a solvent, such as toluene and subjected to carbon monoxide pressure of 25 atmospheres or greater at about 150.degree.-260.degree. C. The reducing metal copper is employed in catalytic concentrations or combined concentrations as CuMoO.sub.4 and both hydrogen and water present serve as promoters. It has been found that the yields by this process have been salutary and that additionally the catalytic metal may be reused in the process to good effect.

  4. Catalytic production of metal carbonyls from metal oxides

    DOE Patents [OSTI]

    Sapienza, R.S.; Slegeir, W.A.; Foran, M.T.

    1984-01-06

    This invention relates to the formation of metal carbonyls from metal oxides and specially the formation of molybdenum carbonyl and iron carbonyl from their respective oxides. Copper is used here in admixed form or used in chemically combined form as copper molybdate. The copper/metal oxide combination or combined copper is utilized with a solvent, such as toluene and subjected to carbon monoxide pressure of 25 atmospheres or greater at about 150 to 260/sup 0/C. The reducing metal copper is employed in catalytic concentrations or combined concentrations as CuMoO/sub 4/ and both hydrogen and water present serve as promoters. It has been found that the yields by this process have been salutary and that additionally the catalytic metal may be reused in the process to good effect. 3 tables.

  5. Process for etching mixed metal oxides

    DOE Patents [OSTI]

    Ashby, C.I.H.; Ginley, D.S.

    1994-10-18

    An etching process is described using dicarboxylic and tricarboxylic acids as chelating etchants for mixed metal oxide films such as high temperature superconductors and ferroelectric materials. Undesirable differential etching rates between different metal oxides are avoided by selection of the proper acid or combination of acids. Feature sizes below one micron, excellent quality vertical edges, and film thicknesses in the 100 Angstrom range may be achieved by this method. 1 fig.

  6. Process for etching mixed metal oxides

    DOE Patents [OSTI]

    Ashby, Carol I. H. (Edgewood, NM); Ginley, David S. (Evergreen, CO)

    1994-01-01

    An etching process using dicarboxylic and tricarboxylic acids as chelating etchants for mixed metal oxide films such as high temperature superconductors and ferroelectric materials. Undesirable differential etching rates between different metal oxides are avoided by selection of the proper acid or combination of acids. Feature sizes below one micron, excellent quality vertical edges, and film thicknesses in the 100 Angstom range may be achieved by this method.

  7. Alkane oxidation with porphyrins and metal complexes thereof having haloalkyl side chains

    DOE Patents [OSTI]

    Wijesekera, Tilak; Lyons, James E.; Ellis, Jr., Paul E.; Bhinde, Manoj V.

    1998-01-01

    Transition metal complexes of meso-haloalkylporphyrins, wherein the haloalkyl groups contain 2 to 8 carbon atoms have been found to be highly effective catalysts for oxidation of alkanes and for the decomposition of hydroperoxides.

  8. Alkane oxidation with porphyrins and metal complexes thereof having haloalkyl side chains

    DOE Patents [OSTI]

    Wijesekera, T.; Lyons, J.E.; Ellis, P.E. Jr.; Bhinde, M.V.

    1998-06-23

    Transition metal complexes of meso-haloalkylporphyrins are disclosed, wherein the haloalkyl groups contain 2 to 8 carbon atoms have been found to be highly effective catalysts for oxidation of alkanes and for the decomposition of hydroperoxides. 7 figs.

  9. High surface area, electrically conductive nanocarbon-supported metal oxide

    DOE Patents [OSTI]

    Worsley, Marcus A.; Han, Thomas Yong-Jin; Kuntz, Joshua D.; Cervantes, Octavio; Gash, Alexander E.; Baumann, Theodore F.; Satcher, Jr., Joe H.

    2015-07-14

    A metal oxide-carbon composite includes a carbon aerogel with an oxide overcoat. The metal oxide-carbon composite is made by providing a carbon aerogel, immersing the carbon aerogel in a metal oxide sol under a vacuum, raising the carbon aerogel with the metal oxide sol to atmospheric pressure, curing the carbon aerogel with the metal oxide sol at room temperature, and drying the carbon aerogel with the metal oxide sol to produce the metal oxide-carbon composite. The step of providing a carbon aerogel can provide an activated carbon aerogel or provide a carbon aerogel with carbon nanotubes that make the carbon aerogel mechanically robust.

  10. High surface area, electrically conductive nanocarbon-supported metal oxide

    DOE Patents [OSTI]

    Worsley, Marcus A; Han, Thomas Yong-Jin; Kuntz, Joshua D; Cervanted, Octavio; Gash, Alexander E; Baumann, Theodore F; Satcher, Jr., Joe H

    2014-03-04

    A metal oxide-carbon composite includes a carbon aerogel with an oxide overcoat. The metal oxide-carbon composite is made by providing a carbon aerogel, immersing the carbon aerogel in a metal oxide sol under a vacuum, raising the carbon aerogel with the metal oxide sol to atmospheric pressure, curing the carbon aerogel with the metal oxide sol at room temperature, and drying the carbon aerogel with the metal oxide sol to produce the metal oxide-carbon composite. The step of providing a carbon aerogel can provide an activated carbon aerogel or provide a carbon aerogel with carbon nanotubes that make the carbon aerogel mechanically robust.

  11. Method for making monolithic metal oxide aerogels

    DOE Patents [OSTI]

    Coronado, Paul R. (Livermore, CA)

    1999-01-01

    Transparent, monolithic metal oxide aerogels of varying densities are produced using a method in which a metal alkoxide solution and a catalyst solution are prepared separately and reacted. The resulting hydrolyzed-condensed colloidal solution is gelled, and the wet gel is contained within a sealed, but gas permeable, containment vessel during supercritical extraction of the solvent. The containment vessel is enclosed within an aqueous atmosphere that is above the supercritical temperature and pressure of the solvent of the metal alkoxide solution.

  12. Proximity-induced magnetism in transition-metal substituted graphene

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | SciTech Connect SciTech Connect Search Results Journal Article: Proximity-induced magnetism in transition-metal substituted graphene Citation Details In-Document Search Title: Proximity-induced magnetism in transition-metal substituted graphene We investigate the interactions between two identical magnetic impurities substituted into a graphene superlattice. Using a first-principles approach, we calculate the electronic and magnetic properties for transition-metal

  13. Tuning of the Metal-Insulator Transition via Alkali Adsorption

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Tuning of the Metal-Insulator Transition via Alkali Adsorption Print Turning a material from an insulator to a metal, or vice versa, by light irradiation, exposure to electric or...

  14. Dislocations and Plasticity in bcc Transition Metals at High...

    Office of Scientific and Technical Information (OSTI)

    Volume 16, Dislocations and Plasticity in bcc Transition Metals at High Pressure, Elsevier, North-Holland, 2010, pp. 1-46 Research Org: Lawrence Livermore National Laboratory...

  15. Probing the surface structure of divalent transition metals using...

    Office of Scientific and Technical Information (OSTI)

    structure of divalent transition metals using surface specific solid-state NMR spectroscopy Citation Details In-Document Search Title: Probing the surface structure of...

  16. Electronic Transitions in f-electron Metals at High Pressures...

    Office of Scientific and Technical Information (OSTI)

    correlation effects that occur in many f-band transition metals and are often ... resonancemore inelastic x-ray spectroscopy and x-ray emission spectroscopy. ...

  17. Large kinetic asymmetry in the metal-insulator transition nucleated...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Large kinetic asymmetry in the metal-insulator transition nucleated at localized and extended defects Citation Details In-Document Search Title: Large kinetic...

  18. Synthesis and Characterization of a Novel Sodium Transition Metal...

    Office of Scientific and Technical Information (OSTI)

    Synthesis and Characterization of a Novel Sodium Transition Metal Oxyfluoride: NaMnMoOsubscript 3Fsubscript 3*Hsubscript 2O Citation Details In-Document Search Title: ...

  19. Probing the surface structure of divalent transition metals using...

    Office of Scientific and Technical Information (OSTI)

    the surface structure of divalent transition metals using surface specific solid-state NMR spectroscopy Citation Details In-Document Search Title: Probing the surface...

  20. A stepwise transition from microporosity to mesoporosity in metal...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    stepwise transition from microporosity to mesoporosity in metal-organic frameworks by thermal treatment Previous Next List Daqiang Yuan, Dan Zhao, Daren J. Timmons and Hong-Cai...

  1. Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2 Print The grand goal motivating femtosecond studies of condensed-matter dynamics is to directly measure the...

  2. A Reversible Crystallinity-Preserving Phase Transition in Metal...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Reversible Crystallinity-Preserving Phase Transition in Metal-Organic Frameworks: Discovery, Mechanistic Studies, and Potential Applications Previous Next List Liu, Dahuan; Liu,...

  3. O3-type layered transition metal oxide Na(NiCoFeTi)1/4O2 as a high rate and long cycle life cathode material for sodium ion batteries

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Yue, Ji -Li; Yang, Xiao -Qing; Zhou, Yong -Ning; Yu, Xiqian; Bak, Seong -Min; Fu, Zheng -Wen

    2015-10-09

    High rate capability and long cycle life are challenging goals for the development of room temperature sodium-ion batteries. Here we report a new single phase quaternary O3-type layer-structured transition metal oxide Na(NiCoFeTi)1/4O2 synthesized by a simple solid-state reaction as a new cathode material for sodium-ion batteries. It can deliver a reversible capacity of 90.6 mA h g–1 at a rate as high as 20C. At 5C, 75.0% of the initial specific capacity can be retained after 400 cycles with a capacity-decay rate of 0.07% per cycle, demonstrating a superior long-term cyclability at high current density. X-ray diffraction and absorption characterizationmore » revealed reversible phase transformations and electronic structural changes during the Na+ deintercalation/intercalation process. Ni, Co and Fe ions contribute to charge compensation during charge and discharge. Although Ti ions do not contribute to the charge transfer, they play a very important role in stabilizing the structure during charge and discharge by suppressing the Fe migration. Additionally, Ti substitution can also smooth the charge–discharge plateaus effectively, which provides a potential advantage for the commercialization of this material for room temperature sodium-ion batteries.« less

  4. O3-type layered transition metal oxide Na(NiCoFeTi)1/4O2 as a high rate and long cycle life cathode material for sodium ion batteries

    SciTech Connect (OSTI)

    Yue, Ji -Li; Yang, Xiao -Qing; Zhou, Yong -Ning; Yu, Xiqian; Bak, Seong -Min; Fu, Zheng -Wen

    2015-10-09

    High rate capability and long cycle life are challenging goals for the development of room temperature sodium-ion batteries. Here we report a new single phase quaternary O3-type layer-structured transition metal oxide Na(NiCoFeTi)1/4O2 synthesized by a simple solid-state reaction as a new cathode material for sodium-ion batteries. It can deliver a reversible capacity of 90.6 mA h g1 at a rate as high as 20C. At 5C, 75.0% of the initial specific capacity can be retained after 400 cycles with a capacity-decay rate of 0.07% per cycle, demonstrating a superior long-term cyclability at high current density. X-ray diffraction and absorption characterization revealed reversible phase transformations and electronic structural changes during the Na+ deintercalation/intercalation process. Ni, Co and Fe ions contribute to charge compensation during charge and discharge. Although Ti ions do not contribute to the charge transfer, they play a very important role in stabilizing the structure during charge and discharge by suppressing the Fe migration. Additionally, Ti substitution can also smooth the chargedischarge plateaus effectively, which provides a potential advantage for the commercialization of this material for room temperature sodium-ion batteries.

  5. Activation of methane by transition metal-substituted aluminophosphate molecular sieves

    DOE Patents [OSTI]

    Iton, Lennox E. (Downers Grove, IL); Maroni, Victor A. (Naperville, IL)

    1991-01-01

    Aluminophosphate molecular sieves substituted with cobalt, manganese or iron and having the AlPO.sub.4 -34 or AlPO.sub.4 -5, or related AlPO.sub.4 structure activate methane starting at approximately 350.degree. C. Between 400.degree. and 500.degree. C. and at methane pressures .ltoreq.1 atmosphere the rate of methane conversion increases steadily with typical conversion efficiencies at 500.degree. C. approaching 50% and selectivity to the production of C.sub.2+ hydrocarbons approaching 100%. The activation mechanism is based on reduction of the transition metal(III) form of the molecular sieve to the transition metal(II) form with accompanying oxidative dehydrogenation of the methane. Reoxidation of the - transition metal(II) form to the transition metal(III) form can be done either chemically (e.g., using O.sub.2) or electrochemically.

  6. A metallic fuel cycle concept from spent oxide fuel to metallic fuel

    SciTech Connect (OSTI)

    Fujita, Reiko; Kawashima, Masatoshi; Yamaoka, Mitsuaki; Arie, Kazuo; Koyama, Tadafumi

    2007-07-01

    A Metallic fuel cycle concept for Self-Consistent Nuclear Energy System (SCNES) has been proposed in a companion papers. The ultimate goal of the SCNES is to realize sustainable energy supply without endangering the environment and humans. For future transition period from LWR era to SCNES era, a new metallic fuel recycle concept from LWR spent fuel has been proposed in this paper. Combining the technology for electro-reduction of oxide fuels and zirconium recovery by electrorefining in molten salts in the nuclear recycling schemes, the amount of radioactive waste reduced in a proposed metallic fuel cycle concept. If the recovery ratio of zirconium metal from the spent zirconium waste is 95%, the cost estimation in zirconium recycle to the metallic fuel materials has been estimated to be less than 1/25. (authors)

  7. Method of making metal oxide ceramic membranes with small pore sizes

    DOE Patents [OSTI]

    Anderson, Marc A. (Madison, WI); Xu, Qunyin (Madison, WI)

    1992-01-01

    A method for the production of metal oxide ceramic membranes is composed of very small pore size. The process is particularly useful in the creation of titanium and other transition metal oxide membranes. The method utilizes a sol-gel process in which the rate of particle formation is controlled by substituting a relatively large alcohol in the metal alkoxide and by limiting the available water. Stable, transparent metal oxide ceramic membranes are created having a narrow distribution of pore size, with the pore diameter being manipulable in the range of 5 to 40 Angstroms.

  8. Metal sulfide initiators for metal oxide sorbent regeneration

    DOE Patents [OSTI]

    Turk, B.S.; Gupta, R.P.

    1999-06-22

    A process of regenerating a sulfided sorbent is provided. According to the process of the invention, a substantial portion of the energy necessary to initiate the regeneration reaction is provided by the combustion of a particulate metal sulfide additive. In using the particulate metal sulfide additive, the oxygen-containing gas used to regenerate the sulfided sorbent can be fed to the regeneration zone without heating or at a lower temperature than used in conventional processes wherein the regeneration reaction is initiated only by heating the oxygen-containing gas. The particulate metal sulfide additive is preferably an inexpensive mineral ore such as iron pyrite which does not adversely affect the regeneration or corresponding desulfurization reactions. The invention further includes a sorbent composition comprising the particulate metal sulfide additive in admixture with an active metal oxide sorbent capable of removing one or more sulfur compounds from a sulfur-containing gas stream. 1 fig.

  9. Metal sulfide initiators for metal oxide sorbent regeneration

    DOE Patents [OSTI]

    Turk, Brian S. (Durham, NC); Gupta, Raghubir P. (Durham, NC)

    2001-01-01

    A process of regenerating a sulfided sorbent is provided. According to the process of the invention, a substantial portion of the energy necessary to initiate the regeneration reaction is provided by the combustion of a particulate metal sulfide additive. In using the particulate metal sulfide additive, the oxygen-containing gas used to regenerate the sulfided sorbent can be fed to the regeneration zone without heating or at a lower temperature than used in conventional processes wherein the regeneration reaction is initiated only by heating the oxygen-containing gas. The particulate metal sulfide additive is preferably an inexpensive mineral ore such as iron pyrite which does not adversely affect the regeneration or corresponding desulfurization reactions. The invention further includes a sorbent composition comprising the particulate metal sulfide additive in admixture with an active metal oxide sorbent capable of removing one or more sulfur compounds from a sulfur-containing gas stream.

  10. Metal sulfide initiators for metal oxide sorbent regeneration

    DOE Patents [OSTI]

    Turk, Brian S. (Durham, NC); Gupta, Raghubir P. (Durham, NC)

    1999-01-01

    A process of regenerating a sulfided sorbent is provided. According to the process of the invention, a substantial portion of the energy necessary to initiate the regeneration reaction is provided by the combustion of a particulate metal sulfide additive. In using the particulate metal sulfide additive, the oxygen-containing gas used to regenerate the sulfided sorbent can be fed to the regeneration zone without heating or at a lower temperature than used in conventional processes wherein the regeneration reaction is initiated only by heating the oxygen-containing. The particulate metal sulfide additive is preferably an inexpensive mineral ore such as iron pyrite which does not adversely affect the regeneration or corresponding desulfurization reactions. The invention further includes a sorbent composition comprising the particulate metal sulfide additive in admixture with an active metal oxide sorbent capable of removing one or more sulfur compounds from a sulfur-containing gas stream.

  11. Reduction of metal oxides through mechanochemical processing

    DOE Patents [OSTI]

    Froes, Francis H. (Moscow, ID); Eranezhuth, Baburaj G. (Moscow, ID); Senkov, Oleg N. (Moscow, ID)

    2000-01-01

    The low temperature reduction of a metal oxide using mechanochemical processing techniques. The reduction reactions are induced mechanically by milling the reactants. In one embodiment of the invention, titanium oxide TiO.sub.2 is milled with CaH.sub.2 to produce TiH.sub.2. Low temperature heat treating, in the range of 400.degree. C. to 700.degree. C., can be used to remove the hydrogen in the titanium hydride.

  12. Tuning of the Metal-Insulator Transition via Alkali Adsorption

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Tuning of the Metal-Insulator Transition via Alkali Adsorption Tuning of the Metal-Insulator Transition via Alkali Adsorption Print Wednesday, 29 March 2006 00:00 Turning a material from an insulator to a metal, or vice versa, by light irradiation, exposure to electric or magnetic fields, or applying small changes in temperature, pressure, or doping-such intriguing control of a material's electronic properties is possible by exploiting strongly interacting or "correlated" electrons.

  13. Transition metal-free olefin polymerization catalyst

    DOE Patents [OSTI]

    Sen, Ayusman (State College, PA); Wojcinski, II, Louis M. (State College, PA); Liu, Shengsheng (State College, PA)

    2001-01-01

    Ethylene and/or propylene are polymerized to form high molecular weight, linear polymers by contacting ethylene and/or propylene monomer, in the presence of an inert reaction medium, with a catalyst system which consists essentially of (1) an aluminum alkyl component, such as trimethylaluminum, triethylaluminum, triisobutylaluminum, tri-n-octylaluminum and diethylaluminum hydride and (2) a Lewis acid or Lewis acid derivative component, such as B (C.sub.6 F.sub.5).sub.3, [(CH.sub.3).sub.2 N (H) (C.sub.6 H.sub.5)].sup.+ [B (C.sub.6 F.sub.5)4].sup.-, [(C.sub.2 H.sub.5).sub.3 NH].sup.+ [B C.sub.6 F.sub.5).sub.4 ],.sup.-, [C(C.sub.6 F.sub.5).sub.3 ].sup.+ [B(C.sub.6 F.sub.5).sub.4 ].sup.-, (C.sub.2 H.sub.5).sub.2 Al(OCH.sub.3), (C.sub.2 H.sub.5).sub.2 Al(2,6-di-t-butyl-4-methylphenoxide), (C.sub.2 H.sub.5)Al(2,6 -di-t-butylphenoxide).sub.2, (C.sub.2 H.sub.5).sub.2 Al(2,6-di-t-butylphonoxide) , 2,6 -di-t-butylphenol.multidot.methylaluminoxane or an alkylaluminoxane, and which may be completely free any transition metal component(s).

  14. Nanostructured Metal Oxide Anodes | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    10 DOE Vehicle Technologies and Hydrogen Programs Annual Merit Review and Peer Evaluation Meeting, June 7-11, 2010 -- Washington D.C. PDF icon es064_dillon_2010_p.pdf More Documents & Publications Atomic Layer Deposition for Stabilization of Amorphous Silicon Anodes Nanostructured Metal Oxide Anodes Novel Lithium Ion Anode Structures: Overview of New DOE BATT Anode Projects

  15. Reactor process using metal oxide ceramic membranes

    DOE Patents [OSTI]

    Anderson, Marc A. (Madison, WI)

    1994-01-01

    A reaction vessel for use in photoelectrochemical reactions includes as its reactive surface a metal oxide porous ceramic membrane of a catalytic metal such as titanium. The reaction vessel includes a light source and a counter electrode. A provision for applying an electrical bias between the membrane and the counter electrode permits the Fermi levels of potential reaction to be favored so that certain reactions may be favored in the vessel. The electrical biasing is also useful for the cleaning of the catalytic membrane. Also disclosed is a method regenerating a porous metal oxide ceramic membrane used in a photoelectrochemical catalytic process by periodically removing the reactants and regenerating the membrane using a variety of chemical, thermal, and electrical techniques.

  16. Reactor process using metal oxide ceramic membranes

    DOE Patents [OSTI]

    Anderson, M.A.

    1994-05-03

    A reaction vessel for use in photoelectrochemical reactions includes as its reactive surface a metal oxide porous ceramic membrane of a catalytic metal such as titanium. The reaction vessel includes a light source and a counter electrode. A provision for applying an electrical bias between the membrane and the counter electrode permits the Fermi levels of potential reaction to be favored so that certain reactions may be favored in the vessel. The electrical biasing is also useful for the cleaning of the catalytic membrane. Also disclosed is a method regenerating a porous metal oxide ceramic membrane used in a photoelectrochemical catalytic process by periodically removing the reactants and regenerating the membrane using a variety of chemical, thermal, and electrical techniques. 2 figures.

  17. Method for producing nanostructured metal-oxides

    DOE Patents [OSTI]

    Tillotson, Thomas M.; Simpson, Randall L.; Hrubesh, Lawrence W.; Gash, Alexander

    2006-01-17

    A synthetic route for producing nanostructure metal-oxide-based materials using sol-gel processing. This procedure employs the use of stable and inexpensive hydrated-metal inorganic salts and environmentally friendly solvents such as water and ethanol. The synthesis involves the dissolution of the metal salt in a solvent followed by the addition of a proton scavenger, which induces gel formation in a timely manner. Both critical point (supercritical extraction) and atmospheric (low temperature evaporation) drying may be employed to produce monolithic aerogels and xerogels, respectively. Using this method synthesis of metal-oxide nanostructured materials have been carried out using inorganic salts, such as of Fe.sup.3+, Cr.sup.3+, Al.sup.3+, Ga.sup.3+, In.sup.3+, Hf.sup.4+, Sn.sup.4+, Zr.sup.4+, Nb.sup.5+, W.sup.6+, Pr.sup.3+, Er.sup.3+, Nd.sup.3+, Ce.sup.3+, U.sup.3+ and Y.sup.3+. The process is general and nanostructured metal-oxides from the following elements of the periodic table can be made: Groups 2 through 13, part of Group 14 (germanium, tin, lead), part of Group 15 (antimony, bismuth), part of Group 16 (polonium), and the lanthanides and actinides. The sol-gel processing allows for the addition of insoluble materials (e.g., metals or polymers) to the viscous sol, just before gelation, to produce a uniformly distributed nanocomposites upon gelation. As an example, energetic nanocomposites of Fe.sub.xO.sub.y gel with distributed Al metal are readily made. The compositions are stable, safe, and can be readily ignited to thermitic reaction.

  18. Microbial-mediated method for metal oxide nanoparticle formation (Patent) |

    Office of Scientific and Technical Information (OSTI)

    SciTech Connect Microbial-mediated method for metal oxide nanoparticle formation Citation Details In-Document Search Title: Microbial-mediated method for metal oxide nanoparticle formation The invention is directed to a method for producing metal oxide nanoparticles, the method comprising: (i) subjecting a combination of reaction components to conditions conducive to microbial-mediated formation of metal oxide nanoparticles, wherein said combination of reaction components comprise:

  19. Reactor vessel using metal oxide ceramic membranes

    DOE Patents [OSTI]

    Anderson, Marc A. (Madison, WI); Zeltner, Walter A. (Oregon, WI)

    1992-08-11

    A reaction vessel for use in photoelectrochemical reactions includes as its reactive surface a metal oxide porous ceramic membrane of a catalytic metal such as titanium. The reaction vessel includes a light source and a counter electrode. A provision for applying an electrical bias between the membrane and the counter electrode permits the Fermi levels of potential reaction to be favored so that certain reactions may be favored in the vessel. The electrical biasing is also useful for the cleaning of the catalytic membrane.

  20. Synthesis of metal silicide at metal/silicon oxide interface by electronic

    Office of Scientific and Technical Information (OSTI)

    excitation (Journal Article) | SciTech Connect Synthesis of metal silicide at metal/silicon oxide interface by electronic excitation Citation Details In-Document Search Title: Synthesis of metal silicide at metal/silicon oxide interface by electronic excitation The synthesis of metal silicide at the metal/silicon oxide interface by electronic excitation was investigated using transmission electron microscopy. A platinum silicide, α-Pt{sub 2}Si, was successfully formed at the

  1. Graphene physics and insulator-metal transition in compressed hydrogen

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    (Journal Article) | DOE PAGES Graphene physics and insulator-metal transition in compressed hydrogen Title: Graphene physics and insulator-metal transition in compressed hydrogen Authors: Naumov, Ivan I. ; Cohen, R. E. ; Hemley, Russell J. Publication Date: 2013-07-22 OSTI Identifier: 1104286 Type: Publisher's Accepted Manuscript Journal Name: Physical Review B Additional Journal Information: Journal Volume: 88; Journal Issue: 4; Journal ID: ISSN 1098-0121 Publisher: American Physical

  2. Probing the surface structure of divalent transition metals using surface

    Office of Scientific and Technical Information (OSTI)

    specific solid-state NMR spectroscopy (Journal Article) | SciTech Connect Probing the surface structure of divalent transition metals using surface specific solid-state NMR spectroscopy Citation Details In-Document Search Title: Probing the surface structure of divalent transition metals using surface specific solid-state NMR spectroscopy Authors: Mason, H E ; Harley, S J ; Maxwell, R S ; Carroll, S A Publication Date: 2011-12-07 OSTI Identifier: 1107317 Report Number(s): LLNL-JRNL-520237

  3. Proximity-induced magnetism in transition-metal substituted graphene

    Office of Scientific and Technical Information (OSTI)

    open Proximity-induced magnetism in transition-metal substituted graphene Received: 23 December 2014 Accepted- 24 June 2015 Charles B. Crook1, Costel Constantin1, Towfiq Ahmed2, Jian-Xin Zhu2-3, Alexander V. Balatsky4,5 & Jason T. Haraldsen1 Published: 03 August 2015 We investigate the interactions between two identical magnetic impurities substituted into a graphene superlattice. Using a first-principles approach, we calculate the electronic and magnetic properties for transition-metal

  4. Extraction of exchange parameters in transition-metal perovskites (Journal

    Office of Scientific and Technical Information (OSTI)

    Article) | SciTech Connect Extraction of exchange parameters in transition-metal perovskites Citation Details In-Document Search This content will become publicly available on September 14, 2016 Title: Extraction of exchange parameters in transition-metal perovskites Authors: Furrer, A. ; Podlesnyak, A. ; Krämer, K. W. Publication Date: 2015-09-15 OSTI Identifier: 1215771 Type: Publisher's Accepted Manuscript Journal Name: Physical Review B Additional Journal Information: Journal Volume:

  5. Graphene physics and insulator-metal transition in compressed hydrogen

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | DOE PAGES Graphene physics and insulator-metal transition in compressed hydrogen Title: Graphene physics and insulator-metal transition in compressed hydrogen Authors: Naumov, Ivan I. ; Cohen, R. E. ; Hemley, Russell J. Publication Date: 2013-07-22 OSTI Identifier: 1104286 Type: Publisher's Accepted Manuscript Journal Name: Physical Review B Additional Journal Information: Journal Volume: 88; Journal Issue: 4; Journal ID: ISSN 1098-0121 Publisher: American Physical

  6. Metal oxide and metal fluoride nanostructures and methods of making same

    DOE Patents [OSTI]

    Wong, Stanislaus S. (Stony Brook, NY); Mao, Yuanbing (Los Angeles, CA)

    2009-08-18

    The present invention includes pure single-crystalline metal oxide and metal fluoride nanostructures, and methods of making same. These nanostructures include nanorods and nanoarrays.

  7. Thermal barrier and overlay coating systems comprising composite metal/metal oxide bond coating layers

    DOE Patents [OSTI]

    Goedjen, John G. (Oviedo, FL); Sabol, Stephen M. (Orlando, FL); Sloan, Kelly M. (Longwood, FL); Vance, Steven J. (Orlando, FL)

    2001-01-01

    The present invention generally describes multilayer coating systems comprising a composite metal/metal oxide bond coat layer. The coating systems may be used in gas turbines.

  8. Method for producing metal oxide aerogels

    DOE Patents [OSTI]

    Tillotson, Thomas M. (Tracy, CA); Poco, John F. (Livermore, CA); Hrubesh, Lawrence W. (Pleasanton, CA); Thomas, Ian M. (Livermore, CA)

    1995-01-01

    A two-step hydrolysis-condensation method was developed to form metal oxide aerogels of any density, including densities of less than 0.003g/cm.sup.3 and greater than 0.27g/cm.sup.3. High purity metal alkoxide is reacted with water, alcohol solvent, and an additive to form a partially condensed metal intermediate. All solvent and reaction-generated alcohol is removed, and the intermediate is diluted with a nonalcoholic solvent. The intermediate can be stored for future use to make aerogels of any density. The aerogels are formed by reacting the intermediate with water, nonalcoholic solvent, and a catalyst, and extracting the nonalcoholic solvent directly. The resulting monolithic aerogels are hydrophobic and stable under atmospheric conditions, and exhibit good optical transparency, high clarity, and homogeneity. The aerogels have high thermal insulation capacity, high porosity, mechanical strength and stability, and require shorter gelation times than aerogels formed by conventional methods.

  9. Method for producing metal oxide aerogels

    DOE Patents [OSTI]

    Tillotson, T.M.; Poco, J.F.; Hrubesh, L.W.; Thomas, I.M.

    1995-04-25

    A two-step hydrolysis-condensation method was developed to form metal oxide aerogels of any density, including densities of less than 0.003g/cm{sup 3} and greater than 0.27g/cm{sup 3}. High purity metal alkoxide is reacted with water, alcohol solvent, and an additive to form a partially condensed metal intermediate. All solvent and reaction-generated alcohol is removed, and the intermediate is diluted with a nonalcoholic solvent. The intermediate can be stored for future use to make aerogels of any density. The aerogels are formed by reacting the intermediate with water, nonalcoholic solvent, and a catalyst, and extracting the nonalcoholic solvent directly. The resulting monolithic aerogels are hydrophobic and stable under atmospheric conditions, and exhibit good optical transparency, high clarity, and homogeneity. The aerogels have high thermal insulation capacity, high porosity, mechanical strength and stability, and require shorter gelation times than aerogels formed by conventional methods. 8 figs.

  10. Using a Semiconductor-to-Metal Transition to Control Optical Transmission through Subwavelength Hole Arrays

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Donev, E. U.; Suh, J. Y.; Lopez, R.; Feldman, L. C.; Haglund, R. F.

    2008-01-01

    We describe a simple configuration in which the extraordinary optical transmission effect through subwavelength hole arrays in noble-metal films can be switched by the semiconductor-to-metal transition in an underlying thin film of vanadium dioxide. In these experiments, the transition is brought about by thermal heating of the bilayer film. The surprising reverse hysteretic behavior of the transmission through the subwavelength holes in the vanadium oxide suggest that this modulation is accomplished by a dielectric-matching condition rather than plasmon coupling through the bilayer film. The results of this switching, including the wavelength dependence, are qualitatively reproduced by a transfer matrix model.more » The prospects for effecting a similar modulation on a much faster time scale by using ultrafast laser pulses to trigger the semiconductor-to-metal transition are also discussed.« less

  11. Method for inhibiting oxidation of metal sulfide-containing material

    DOE Patents [OSTI]

    Elsetinow, Alicia; Borda, Michael J.; Schoonen, Martin A.; Strongin, Daniel R.

    2006-12-26

    The present invention provides means for inhibiting the oxidation of a metal sulfide-containing material, such as ore mine waste rock or metal sulfide taiulings, by coating the metal sulfide-containing material with an oxidation-inhibiting two-tail lipid coating (12) thereon, thereby inhibiting oxidation of the metal sulfide-containing material in acid mine drainage conditions. The lipids may be selected from phospholipids, sphingolipids, glycolipids and combinations thereof.

  12. Electronic Spin Transition in Nanosize Stoichiometric Lithium Cobalt Oxide

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | SciTech Connect SciTech Connect Search Results Journal Article: Electronic Spin Transition in Nanosize Stoichiometric Lithium Cobalt Oxide Citation Details In-Document Search Title: Electronic Spin Transition in Nanosize Stoichiometric Lithium Cobalt Oxide Authors: Qian, Danna ; Hinuma, Yoyo ; Chen, Hailong ; Du, Lin-Shu ; Carroll, Kyler J. ; Ceder, Gerbrand ; Grey, Clare P. ; Meng, Ying S. Publication Date: 2012-04-11 OSTI Identifier: 1066375 DOE Contract Number:

  13. Thermally stable crystalline mesoporous metal oxides with substantially uniform pores

    DOE Patents [OSTI]

    Wiesner, Ulrich; Orilall, Mahendra Christopher; Lee, Jinwoo; DiSalvo, Jr., Francis J

    2015-01-27

    Highly crystalline metal oxide-carbon composites, as precursors to thermally stable mesoporous metal oxides, are coated with a layer of amorphous carbon. Using a `one-pot` method, highly crystalline metal oxide-carbon composites are converted to thermally stable mesoporous metal oxides, having highly crystalline mesopore walls, without causing the concomitant collapse of the mesostructure. The `one-pot` method uses block copolymers with an sp or sp 2 hybridized carbon containing hydrophobic block as structure directing agents which converts to a sturdy, amorphous carbon material under appropriate heating conditions, providing an in-situ rigid support which maintains the pores of the oxides intact while crystallizing at temperatures as high as 1000 deg C. A highly crystalline metal oxide-carbon composite can be heated to produce a thermally stable mesoporous metal oxide consisting of a single polymorph.

  14. Flexible metallic seal for transition duct in turbine system

    DOE Patents [OSTI]

    Flanagan, James Scott; LeBegue, Jeffrey Scott; McMahan, Kevin Weston; Dillard, Daniel Jackson; Pentecost, Ronnie Ray

    2014-04-22

    A turbine system is disclosed. In one embodiment, the turbine system includes a transition duct. The transition duct includes an inlet, an outlet, and a passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of the transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The transition duct further includes an interface member for interfacing with a turbine section. The turbine system further includes a flexible metallic seal contacting the interface member to provide a seal between the interface member and the turbine section.

  15. Polymer-assisted aqueous deposition of metal oxide films

    DOE Patents [OSTI]

    Li, DeQuan (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM)

    2003-07-08

    An organic solvent-free process for deposition of metal oxide thin films is presented. The process includes aqueous solutions of necessary metal precursors and an aqueous solution of a water-soluble polymer. After a coating operation, the resultant coating is fired at high temperatures to yield optical quality metal oxide thin films.

  16. Preferential orientation of metal oxide superconducting materials

    DOE Patents [OSTI]

    Capone, Donald W. (Bolingbrook, IL); Poeppel, Roger B. (Glen Ellyn, IL)

    1991-01-01

    A polycrystalline metal oxide such as YBa.sub.2 Cu.sub.3 O.sub.7-X (where 0

  17. Metal oxide membranes for gas separation

    DOE Patents [OSTI]

    Anderson, M.A.; Webster, E.T.; Xu, Q.

    1994-08-30

    A method for formation of a microporous ceramic membrane onto a porous support includes placing a colloidal suspension of metal oxide particles on one side of the porous support and exposing the other side of the porous support to a drying stream of gas or a reactive gas stream so that the particles are deposited on the drying side of the support as a gel. The gel so deposited can be sintered to form a supported ceramic membrane having mean pore sizes less than 30 Angstroms and useful for ultrafiltration, reverse osmosis, or gas separation. 4 figs.

  18. Metal oxide membranes for gas separation

    DOE Patents [OSTI]

    Anderson, Marc A. (Madison, WI); Webster, Elizabeth T. (Madison, WI); Xu, Qunyin (Plainsboro, NJ)

    1994-01-01

    A method for permformation of a microporous ceramic membrane onto a porous support includes placing a colloidal suspension of metal oxide particles on one side of the porous support and exposing the other side of the porous support to a drying stream of gas or a reactive gas stream so that the particles are deposited on the drying side of the support as a gel. The gel so deposited can be sintered to form a supported ceramic membrane having mean pore sizes less than 30 Angstroms and useful for ultrafiltration, reverse osmosis, or gas separation.

  19. Memristor using a transition metal nitride insulator

    DOE Patents [OSTI]

    Stevens, James E; Marinella, Matthew; Lohn, Andrew John

    2014-10-28

    Apparatus is disclosed in which at least one resistive switching element is interposed between at least a first and a second conducting electrode element. The resistive switching element comprises a metal oxynitride. A method for making such a resistive switching element is also disclosed.

  20. Nanodisperse transition metal electrodes (NTME) for electrochemical cells

    DOE Patents [OSTI]

    Striebel, Kathryn A. (Oakland, CA); Wen, Shi-Jie (Sunnyvale, CA)

    2000-01-01

    Disclosed are transition metal electrodes for electrochemical cells using gel-state and solid-state polymers. The electrodes are suitable for use in primary and secondary cells. The electrodes (either negative electrode or positive electrode) are characterized by uniform dispersion of the transition metal at the nanoscale in the polymer. The transition metal moiety is structurally amorphous, so no capacity fade should occur due to lattice expansion/contraction mechanisms. The small grain size, amorphous structure and homogeneous distribution provide improved charge/discharge cycling performance, and a higher initial discharge rate capability. The cells can be cycled at high current densities, limited only by the electrolyte conductivity. A method of making the electrodes (positive and negative), and their usage in electrochemical cells are disclosed.

  1. [Transition metal mediated transformations of small molecules]. Progress report

    SciTech Connect (OSTI)

    Sen, A.

    1992-10-01

    Work on organotransition metal chemistry, homogeneous and heterogeneous catalysis is summarized. Several cationic palladium(II) complexes with bulky phosphine or pyridine ligands were discovered that are highly selective catalysts for linear dimerization of vinyl monomers and linear polymerization of p-divinylbenzene, the reactions proceeding through a carbocationic mechanism. Our studies were continued on alternating olefin-carbon monoxide copolymers. The copolymerization reaction and reactivity of copolymers were examined. New catalytic systems for alternating copolymerization of {alpha}-olefins with CO were discovered. In the case of styrene derivatives, tactic copolymers were obtained. Poly(ethylenepyrrolediyl) derivatives were synthesized from alternating ethylene-carbon monoxide copolymer and become electronic conductors when doped with iodine. A catalytic system for direct synthesis of polyureas and polyoxamides from and diamines was also discovered. Pt metal catalyzed the oxidation of ethers, esters, and amines to carboxylic acids and the oxidation of olefins to 1,2-diols. Anaerobic and aerobic decomposition of molybdenum(VI)-oxoalkyl compounds were studied for heterogeneous oxidation of alkanes and olefins on Mo(VI)-oxide surfaces. Synthesis of polymer-trapped metal, metal oxide, and metal sulfide nanoclusters (size <1--10 nm) was studied.

  2. Synthesis and Characterization of a Novel Sodium Transition Metal

    Office of Scientific and Technical Information (OSTI)

    Oxyfluoride: NaMnMoO[subscript 3]F[subscript 3]*H[subscript 2]O (Journal Article) | SciTech Connect Synthesis and Characterization of a Novel Sodium Transition Metal Oxyfluoride: NaMnMoO[subscript 3]F[subscript 3]*H[subscript 2]O Citation Details In-Document Search Title: Synthesis and Characterization of a Novel Sodium Transition Metal Oxyfluoride: NaMnMoO[subscript 3]F[subscript 3]*H[subscript 2]O Authors: Nava-Avendaño, Jessica ; Frontera, Carlos ; Ayllón, José A. ; Oró-Solé, Judith

  3. Vehicle Technologies Office Merit Review 2015: Metal Oxide Nano...

    Office of Environmental Management (EM)

    based Monolithic Catalysts Monolithic Metal Oxide based Composite Nanowire Lean NOx Emission Control Catalysts Three-Dimensional Composite Nanostructures for Lean NOx...

  4. Additional capacities seen in metal oxide lithium-ion battery...

    Office of Scientific and Technical Information (OSTI)

    SciTech Connect Search Results Journal Article: Additional capacities seen in metal oxide lithium-ion battery electrodes Citation Details In-Document Search Title: Additional ...

  5. Thermochemical cycle of a mixed metal oxide for augmentation...

    Office of Scientific and Technical Information (OSTI)

    Thermochemical cycle of a mixed metal oxide for augmentation of thermal energy storage in solid particles. Citation Details In-Document Search Title: Thermochemical cycle of a ...

  6. Tuning of the Metal-Insulator Transition via Alkali Adsorption

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Tuning of the Metal-Insulator Transition via Alkali Adsorption Print Turning a material from an insulator to a metal, or vice versa, by light irradiation, exposure to electric or magnetic fields, or applying small changes in temperature, pressure, or doping-such intriguing control of a material's electronic properties is possible by exploiting strongly interacting or "correlated" electrons. Now a team of researchers from the University of Kiel in Germany and the ALS has found a novel,

  7. Tuning of the Metal-Insulator Transition via Alkali Adsorption

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Tuning of the Metal-Insulator Transition via Alkali Adsorption Print Turning a material from an insulator to a metal, or vice versa, by light irradiation, exposure to electric or magnetic fields, or applying small changes in temperature, pressure, or doping-such intriguing control of a material's electronic properties is possible by exploiting strongly interacting or "correlated" electrons. Now a team of researchers from the University of Kiel in Germany and the ALS has found a novel,

  8. Tuning of the Metal-Insulator Transition via Alkali Adsorption

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Tuning of the Metal-Insulator Transition via Alkali Adsorption Print Turning a material from an insulator to a metal, or vice versa, by light irradiation, exposure to electric or magnetic fields, or applying small changes in temperature, pressure, or doping-such intriguing control of a material's electronic properties is possible by exploiting strongly interacting or "correlated" electrons. Now a team of researchers from the University of Kiel in Germany and the ALS has found a novel,

  9. Redox chemistry and metal-insulator transitions intertwined in a

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    nano-porous material | Center for Gas SeparationsRelevant to Clean Energy Technologies | Blandine Jerome Redox chemistry and metal-insulator transitions intertwined in a nano-porous material Previous Next List Sergey N. Maximoff and Berend Smit, Nature Communications 5, 4032 (2014) DOI: 10.1038/ncomms5032 Abstract: Metal-organic frameworks are nano-porous adsorbents of relevance to gas separation and catalysis, and separation of oxygen from air is essential to diverse industrial

  10. Method of synthesizing bulk transition metal carbide, nitride and phosphide catalysts

    DOE Patents [OSTI]

    Choi, Jae Soon; Armstrong, Beth L; Schwartz, Viviane

    2015-04-21

    A method for synthesizing catalyst beads of bulk transmission metal carbides, nitrides and phosphides is provided. The method includes providing an aqueous suspension of transition metal oxide particles in a gel forming base, dropping the suspension into an aqueous solution to form a gel bead matrix, heating the bead to remove the binder, and carburizing, nitriding or phosphiding the bead to form a transition metal carbide, nitride, or phosphide catalyst bead. The method can be tuned for control of porosity, mechanical strength, and dopant content of the beads. The produced catalyst beads are catalytically active, mechanically robust, and suitable for packed-bed reactor applications. The produced catalyst beads are suitable for biomass conversion, petrochemistry, petroleum refining, electrocatalysis, and other applications.

  11. Method of producing solution-derived metal oxide thin films

    DOE Patents [OSTI]

    Boyle, Timothy J. (Albuquerque, NM); Ingersoll, David (Albuquerque, NM)

    2000-01-01

    A method of preparing metal oxide thin films by a solution method. A .beta.-metal .beta.-diketonate or carboxylate compound, where the metal is selected from groups 8, 9, 10, 11, and 12 of the Periodic Table, is solubilized in a strong Lewis base to form a homogeneous solution. This precursor solution forms within minutes and can be deposited on a substrate in a single layer or a multiple layers to form a metal oxide thin film. The substrate with the deposited thin film is heated to change the film from an amorphous phase to a ceramic metal oxide and cooled.

  12. Molten salt extraction process for the recovery of valued transition metals from land-based and deep-sea minerals

    DOE Patents [OSTI]

    Maroni, V.A.; von Winbush, S.

    1987-05-01

    A process for extracting transition metals and particularly cobalt and manganese together with iron, copper and nickel from low grade ores (including ocean-floor nodules) by converting the metal oxides or other compositions to chlorides in a molten salt, and subsequently using a combination of selective distillation at temperatures below about 500/degree/C, electrolysis at a voltage not more negative that about /minus/1.5 volt versus Ag/AgCl, and precipitation to separate the desired manganese and cobalt salts from other metals and provide cobalt and manganese in metallic forms or compositions from which these metals may be more easily recovered.

  13. Molten salt extraction process for the recovery of valued transition metals from land-based and deep-sea minerals

    DOE Patents [OSTI]

    Maroni, Victor A. (Naperville, IL); von Winbush, Samuel (Huntington, NY)

    1988-01-01

    A process for extracting transition metals and particularly cobalt and manganese together with iron, copper and nickel from low grade ores (including ocean-floor nodules) by converting the metal oxides or other compositions to chlorides in a molten salt, and subsequently using a combination of selective distillation at temperatures below about 500.degree. C., electrolysis at a voltage not more negative than about -1.5 volt versus Ag/AgCl, and precipitation to separate the desired manganese and cobalt salts from other metals and provide cobalt and manganese in metallic forms or compositions from which these metals may be more easily recovered.

  14. Defect Chemistry and Plasmon Physics of Colloidal Metal Oxide Nanocrystals

    SciTech Connect (OSTI)

    Lounis, SD; Runnerstrorm, EL; Llordes, A; Milliron, DJ

    2014-05-01

    Plasmonic nanocrystals of highly doped metal oxides have seen rapid development in the past decade and represent a class of materials with unique optoelectronic properties. In this Perspective, we discuss doping mechanisms in metal oxides and the accompanying physics of free carrier scattering, both of which have implications in determining the properties of localized surface plasmon resonances (LSPRs) in these nanocrystals. The balance between activation and compensation of dopants limits the free carrier concentration of the most common metal oxides, placing a ceiling on the LSPR frequency. Furthermore, because of ionized impurity scattering of the oscillating plasma by dopant ions, scattering must be treated in a fundamentally different way in semiconductor metal oxide materials when compared with conventional metals. Though these effects are well-understood in bulk metal oxides, further study is needed to understand their manifestation in nanocrystals and corresponding impact on plasmonic properties, and to develop materials that surpass current limitations in free carrier concentration.

  15. Preparation of nanoporous metal foam from high nitrogen transition metal complexes

    DOE Patents [OSTI]

    Tappan, Bryce C.; Huynh, My Hang V.; Hiskey, Michael A.; Son, Steven F.; Oschwald, David M.; Chavez, David E.; Naud, Darren L.

    2006-11-28

    Nanoporous metal foams are prepared by ignition of high nitrogen transition metal complexes. The ammonium salts of iron(III) tris[bi(tetrazolato)-amine], cobalt(III) tris(bi(tetrazolato)amine), and high nitrogen compounds of copper and silver were prepared as loose powders, pressed into pellets and wafers, and ignited under an inert atmosphere to form nanoporous metal foam monoliths having very high surface area and very low density.

  16. The transition to the metallic state in low density hydrogen

    SciTech Connect (OSTI)

    McMinis, Jeremy; Morales, Miguel A.; Ceperley, David M.; Kim, Jeongnim

    2015-11-18

    Solid atomic hydrogen is one of the simplest systems to undergo a metal-insulator transition. Near the transition, the electronic degrees of freedom become strongly correlated and their description provides a difficult challenge for theoretical methods. As a result, the order and density of the phase transition are still subject to debate. In this work we use diffusion quantum Monte Carlo to benchmark the transition between the paramagnetic and anti-ferromagnetic phases of ground state body centered cubic atomic hydrogen. We locate the density of the transition by computing the equation of state for these two phases and identify the phase transition order by computing the band gap near the phase transition. These benchmark results show that the phase transition is continuous and occurs at a Wigner-Seitz radius of rs = 2.27(3)a0. As a result, we compare our results to previously reported density functional theory, Hedin s GW approximation, and dynamical mean field theory results.

  17. Solder for oxide layer-building metals and alloys

    DOE Patents [OSTI]

    Kronberg, J.W.

    1992-09-15

    A low temperature solder and method for soldering an oxide layer-building metal such as aluminum, titanium, tantalum or stainless steel is disclosed. The composition comprises tin and zinc; germanium as a wetting agent; preferably small amounts of copper and antimony; and a grit, such as silicon carbide. The grit abrades any oxide layer formed on the surface of the metal as the germanium penetrates beneath and loosens the oxide layer to provide good metal-to-metal contact. The germanium comprises less than approximately 10% by weight of the solder composition so that it provides sufficient wetting action but does not result in a melting temperature above approximately 300 C. The method comprises the steps rubbing the solder against the metal surface so the grit in the solder abrades the surface while heating the surface until the solder begins to melt and the germanium penetrates the oxide layer, then brushing aside any oxide layer loosened by the solder.

  18. Solder for oxide layer-building metals and alloys

    DOE Patents [OSTI]

    Kronberg, James W. (108 Independent Blvd., Aiken, SC 29801)

    1992-01-01

    A low temperature solder and method for soldering an oxide layer-building metal such as aluminum, titanium, tantalum or stainless steel. The comosition comprises tin and zinc; germanium as a wetting agent; preferably small amounts of copper and antimony; and a grit, such as silicon carbide. The grit abrades any oxide layer formed on the surface of the metal as the germanium penetrates beneath and loosens the oxide layer to provide good metal-to-metal contact. The germanium comprises less than aproximatley 10% by weight of the solder composition so that it provides sufficient wetting action but does not result in a melting temperature above approximately 300.degree. C. The method comprises the steps rubbing the solder against the metal surface so the grit in the solder abrades the surface while heating the surface until the solder begins to melt and the germanium penetrates the oxide layer, then brushing aside any oxide layer loosened by the solder.

  19. Metal Current Collector Protected by Oxide Film - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Metal Current Collector Protected by Oxide Film Lawrence Berkeley National Laboratory Contact LBL About This Technology Technology Marketing SummarySteven Visco, Craig Jacobson, and Lutgard DeJonghe have designed a cost-efficient, structurally sound technology for current collection and cell-to-cell interconnection of high temperature (>600 C) planar electrochemical devices. Current collection is normally achieved using expensive metal oxides or metals such as platinum or nickel.

  20. Oxidized film structure and method of making epitaxial metal oxide structure

    DOE Patents [OSTI]

    Gan, Shupan [Richland, WA; Liang, Yong [Richland, WA

    2003-02-25

    A stable oxidized structure and an improved method of making such a structure, including an improved method of making an interfacial template for growing a crystalline metal oxide structure, are disclosed. The improved method comprises the steps of providing a substrate with a clean surface and depositing a metal on the surface at a high temperature under a vacuum to form a metal-substrate compound layer on the surface with a thickness of less than one monolayer. The compound layer is then oxidized by exposing the compound layer to essentially oxygen at a low partial pressure and low temperature. The method may further comprise the step of annealing the surface while under a vacuum to further stabilize the oxidized film structure. A crystalline metal oxide structure may be subsequently epitaxially grown by using the oxidized film structure as an interfacial template and depositing on the interfacial template at least one layer of a crystalline metal oxide.

  1. The transition to the metallic state in low density hydrogen

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    McMinis, Jeremy; Morales, Miguel A.; Ceperley, David M.; Kim, Jeongnim

    2015-11-18

    Solid atomic hydrogen is one of the simplest systems to undergo a metal-insulator transition. Near the transition, the electronic degrees of freedom become strongly correlated and their description provides a difficult challenge for theoretical methods. As a result, the order and density of the phase transition are still subject to debate. In this work we use diffusion quantum Monte Carlo to benchmark the transition between the paramagnetic and anti-ferromagnetic phases of ground state body centered cubic atomic hydrogen. We locate the density of the transition by computing the equation of state for these two phases and identify the phase transitionmore » order by computing the band gap near the phase transition. These benchmark results show that the phase transition is continuous and occurs at a Wigner-Seitz radius of rs = 2.27(3)a0. As a result, we compare our results to previously reported density functional theory, Hedin s GW approximation, and dynamical mean field theory results.« less

  2. High-Temperature Zirconia Oxygen Sensor with Sealed Metal/Metal Oxide

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Internal Reference | Department of Energy High-Temperature Zirconia Oxygen Sensor with Sealed Metal/Metal Oxide Internal Reference High-Temperature Zirconia Oxygen Sensor with Sealed Metal/Metal Oxide Internal Reference Poster presentation at the 2007 Diesel Engine-Efficiency & Emissions Research Conference (DEER 2007). 13-16 August, 2007, Detroit, Michigan. Sponsored by the U.S. Department of Energy's (DOE) Office of FreedomCAR and Vehicle Technologies (OFCVT). PDF icon

  3. Catalysis using hydrous metal oxide ion exchanges

    DOE Patents [OSTI]

    Dosch, Robert G. (Albuquerque, NM); Stephens, Howard P. (Albuquerque, NM); Stohl, Frances V. (Albuquerque, NM)

    1985-01-01

    In a process which is catalyzed by a catalyst comprising an active metal on a carrier, said metal being active as a catalyst for the process, an improvement is provided wherein the catalyst is a hydrous, alkali metal or alkaline earth metal titanate, zirconate, niobate or tantalate wherein alkali or alkaline earth metal cations have been exchanged with a catalytically effective amount of cations of said metal.

  4. Catalysis using hydrous metal oxide ion exchangers

    DOE Patents [OSTI]

    Dosch, R.G.; Stephens, H.P.; Stohl, F.V.

    1983-07-21

    In a process which is catalyzed by a catalyst comprising an active metal on a carrier, said metal being active as a catalyst for the process, an improvement is provided wherein the catalyst is a hydrous, alkali metal or alkaline earth metal titanate, zirconate, niobate or tantalate wherein alkali or alkaline earth metal cations have been exchanged with a catalytically effective amount of cations of said metal.

  5. Reduction of spalling in mixed metal oxide desulfurization sorbents by addition of a large promoter metal oxide

    DOE Patents [OSTI]

    Poston, James A. (Star City, WV)

    1997-01-01

    Mixed metal oxide pellets for removing hydrogen sulfide from fuel gas mixes derived from coal are stabilized for operation over repeated cycles of desulfurization and regeneration reactions by addition of a large promoter metal oxide such as lanthanum trioxide. The pellets, which may be principally made up of a mixed metal oxide such as zinc titanate, exhibit physical stability and lack of spalling or decrepitation over repeated cycles without loss of reactivity. The lanthanum oxide is mixed with pellet-forming components in an amount of 1 to 10 weight percent.

  6. Reduction of spalling in mixed metal oxide desulfurization sorbents by addition of a large promoter metal oxide

    DOE Patents [OSTI]

    Poston, J.A.

    1997-12-02

    Mixed metal oxide pellets for removing hydrogen sulfide from fuel gas mixes derived from coal are stabilized for operation over repeated cycles of desulfurization and regeneration reactions by addition of a large promoter metal oxide such as lanthanum trioxide. The pellets, which may be principally made up of a mixed metal oxide such as zinc titanate, exhibit physical stability and lack of spalling or decrepitation over repeated cycles without loss of reactivity. The lanthanum oxide is mixed with pellet-forming components in an amount of 1 to 10 weight percent.

  7. Evidence of transition-metal accumulation on aged graphite anodes by SIMS.

    SciTech Connect (OSTI)

    Abraham, D. P.; Spila, T.; Furczon, M. M.; Sammann, E.; Chemical Sciences and Engineering Division; Univ. of Illinois

    2008-01-01

    In cells containing Li{sub 1.05}(Ni{sub 1/3}Co{sub 1/3}Mn{sub 1/3}){sub 0.95}O{sub 2}-based positive and graphite-based negative electrodes, a significant portion of cell impedance rise on aging is known to be from the negative electrode. One possible reason for this impedance rise is the dissolution of transition-metal elements from the oxide electrode that accumulate and create a high-impedance layer at the negative electrode-electrolyte interface. This article details dynamic secondary ion mass spectrometry (SIMS) measurements, which provide a relative comparison of Mn, Co, and Ni contents on fresh, formed, and aged graphite electrodes. The data clearly indicate that these transition-metal elements accumulate at the electrode surface and diffuse into the electrode during cell aging.

  8. Cross-linking proteins with bimetallic tetracarboxylate compounds of transition metals

    DOE Patents [OSTI]

    Kostic, Nenad M. (Ames, IA); Chen, Jian (Ames, IA)

    1991-03-05

    Stable cross-linked complexes of transition-metal tetracarboxylates and proteins are formed. The preferred transition-metal is rhodium. The protein may be collagen or an enzyme such as a proteolytic enzyme.

  9. Cross-linking proteins with bimetallic tetracarboxylate compounds of transition metals

    DOE Patents [OSTI]

    Kostic, N.M.; Chen, J.

    1991-03-05

    Stable cross-linked complexes of transition-metal tetracarboxylates and proteins are formed. The preferred transition-metal is rhodium. The protein may be collagen or an enzyme such as a proteolytic enzyme. No Drawings

  10. Transition metal catalysis in the generation of natural gas

    SciTech Connect (OSTI)

    Mango, F.D.

    1995-12-31

    The view that natural gas is thermolytic, coming from decomposing organic debris, has remained almost unchallenged for nearly half a century. Disturbing contradictions exist, however: Oil is found at great depth, at temperatures where only gas should exist and oil and gas deposits show no evidence of the thermolytic debris indicative of oil decomposing to gas. Moreover, laboratory attempts to duplicate the composition of natural gas, which is typically between 60 and 95+ wt% methane in C{sub 1}-C{sub 4}, have produced insufficient amounts of methane (10 to 60%). It has been suggested that natural gas may be generated catalytically, promoted by the transition metals in carbonaceous sedimentary rocks. This talk will discuss experimental results that support this hypothesis. Various transition metals, as pure compounds and in source rocks, will be shown to generate a catalytic gas that is identical to natural gas. Kinetic results suggest robust catalytic activity under moderate catagenetic conditions.

  11. CO oxidation on gold-supported iron oxides: New insights into strong oxidemetal interactions

    SciTech Connect (OSTI)

    Yu, Liang; Liu, Yun; Yang, Fan; Evans, Jaime; Rodriguez, Jos A.; Liu, Ping

    2015-07-14

    Very active FeOxAu catalysts for CO oxidation are obtained after depositing nanoparticles of FeO, Fe3O4, and Fe2O3 on a Au(111) substrate. Neither FeO nor Fe2O3 is stable under the reaction conditions. Under an environment of CO/O2, they undergo oxidation (FeO) or reduction (Fe2O3) to yield nanoparticles of Fe3O4 that are not formed in a bulk phase. Using a combined experimental and theoretical approach, we show a strong oxidemetal interaction (SOMI) between Fe3O4 nanostructures and Au(111), which gives the oxide special properties, allows the formation of an active phase, and provides a unique interface to facilitate a catalytic reaction. This work highlights the important role that the SOMI can play in enhancing the catalytic performance of the oxide component in metaloxide catalysts.

  12. Method for converting uranium oxides to uranium metal

    DOE Patents [OSTI]

    Duerksen, Walter K. (Norris, TN)

    1988-01-01

    A process is described for converting scrap and waste uranium oxide to uranium metal. The uranium oxide is sequentially reduced with a suitable reducing agent to a mixture of uranium metal and oxide products. The uranium metal is then converted to uranium hydride and the uranium hydride-containing mixture is then cooled to a temperature less than -100.degree. C. in an inert liquid which renders the uranium hydride ferromagnetic. The uranium hydride is then magnetically separated from the cooled mixture. The separated uranium hydride is readily converted to uranium metal by heating in an inert atmosphere. This process is environmentally acceptable and eliminates the use of hydrogen fluoride as well as the explosive conditions encountered in the previously employed bomb-reduction processes utilized for converting uranium oxides to uranium metal.

  13. Zwitterionic Group VIII transition metal initiators supported by olefin ligands

    DOE Patents [OSTI]

    Bazan, Guillermo C. (Goleta, CA); Chen, Yaofeng (Shanghai, CN)

    2011-10-25

    A zwitterionic Group VIII transition metal complex containing the simple and relatively small 3-(arylimino)-but-1-en-2-olato ligand that catalyzes the formation of polypropylene and high molecular weight polyethylene. A novel feature of this catalyst is that the active species is stabilized by a chelated olefin adduct. The present invention also provides methods of polymerizing olefin monomers using zwitterionic catalysts, particularly polypropylene and high molecular weight polyethylene.

  14. Method and apparatus for the production of metal oxide powder

    DOE Patents [OSTI]

    Harris, M.T.; Scott, T.C.; Byers, C.H.

    1992-06-16

    The present invention provides a method for preparing metal oxide powder. A first solution, which is substantially organic, is prepared. A second solution, which is an aqueous solution substantially immiscible in the first solution, is prepared and delivered as drops to the first solution. The drops of the second solution are atomized by a pulsed electric field forming micro-drops of the second solution. Reagents in the first solution diffuse into and react with reactants in the micro-drops of the second solution forming metal hydroxide or oxalate particles. The metal hydroxide or metal oxalate particles are then recovered and dried to produce the metal oxide powder. An apparatus for preparing a metal oxide powder is also disclosed. 2 figs.

  15. Method and apparatus for the production of metal oxide powder

    DOE Patents [OSTI]

    Harris, Michael T. (Knoxville, TN); Scott, Timothy C. (Knoxville, TN); Byers, Charles H. (Oak Ridge, TN)

    1992-01-01

    The present invention provides a method for preparing metal oxide powder. A first solution, which is substantially organic, is prepared. A second solution, which is an aqueous solution substantially immiscible in the first solution, is prepared and delivered as drops to the first solution. The drops of the second solution are atomized by a pulsed electric field forming micro-drops of the second solution. Reagents in the first solution diffuse into and react with reactants in the micro-drops of the second solution forming metal hydroxide or oxalate particles. The metal hydroxide or metal oxalate particles are then recovered and dried to produce the metal oxide powder. An apparatus for preparing a metal oxide powder is also disclosed.

  16. Method and apparatus for the production of metal oxide powder

    DOE Patents [OSTI]

    Harris, Michael T. (Knoxville, TN); Scott, Timothy C. (Knoxville, TN); Byers, Charles H. (Oak Ridge, TN)

    1993-01-01

    The present invention provides a method for preparing metal oxide powder. A first solution, which is substantially organic, is prepared. A second solution, which is an aqueous solution substantially immiscible in the first solution, is prepared and delivered as drops to the first solution. The drops of the second solution are atomized by a pulsed electric field forming micro-drops of the second solution. Reagents in the first solution diffuse into and react with reactants in the micro-drops of the second solution forming metal hydroxide or oxalate particles. The metal hydroxide or metal oxalate particles are then recovered and dried to produce the metal oxide powder. An apparatus for preparing a metal oxide powder is also disclosed.

  17. NREL Demonstrates Efficient Solar Water Splitting by Metal Oxide Photoabsorber (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2014-01-01

    New development demonstrates that inexpensive and robust metal oxide photoabsorbers hold great promise as photoanodes for water oxidation.

  18. Method for treating rare earth-transition metal scrap

    DOE Patents [OSTI]

    Schmidt, Frederick A. (Ames, IA); Peterson, David T. (Ames, IA); Wheelock, John T. (Nevada, IA); Jones, Lawrence L. (Des Moines, IA)

    1992-12-29

    Rare earth-transition metal (e.g., iron) scrap (e.g., Nd-Fe-B scrap) is flux (slag) remelted to reduce tramp non-metallic impurities, such as oxygen and nitrogen, and metallic impurities, such as Li, Na, Al, etc., picked up by the scrap from previous fabrication operations. The tramp impurities are reduced to concentrations acceptable for reuse of the treated alloy in the manufacture of end-use articles, such as permanent magnets. The scrap is electroslag or inductoslag melted using a prefused, rare earth fluoride-bearing flux of CaF.sub.2, CaCl.sub.2 or mixtures thereof or the slag resulting from practice of the thermite reduction process to make a rare earth-iron alloy.

  19. Method for treating rare earth-transition metal scrap

    DOE Patents [OSTI]

    Schmidt, F.A.; Peterson, D.T.; Wheelock, J.T.; Jones, L.L.

    1992-12-29

    Rare earth-transition metal (e.g., iron) scrap (e.g., Nd-Fe-B scrap) is flux (slag) remelted to reduce tramp non-metallic impurities, such as oxygen and nitrogen, and metallic impurities, such as Li, Na, Al, etc., picked up by the scrap from previous fabrication operations. The tramp impurities are reduced to concentrations acceptable for reuse of the treated alloy in the manufacture of end-use articles, such as permanent magnets. The scrap is electroslag or inductoslag melted using a rare earth fluoride-bearing flux of CaF[sub 2], CaCl[sub 2] or mixtures thereof or the slag resulting from practice of the thermite reduction process to make a rare earth-iron alloy. 3 figs.

  20. Inert electrode containing metal oxides, copper and noble metal

    DOE Patents [OSTI]

    Ray, Siba P. (Murrysville, PA); Woods, Robert W. (New Kensington, PA); Dawless, Robert K. (Monroeville, PA); Hosler, Robert B. (Sarver, PA)

    2000-01-01

    A cermet composite material is made by treating at an elevated temperature a mixture comprising a compound of iron and a compound of at least one other metal, together with an alloy or mixture of copper and a noble metal. The alloy or mixture preferably comprises particles having an interior portion containing more copper than noble metal and an exterior portion containing more noble metal than copper. The noble metal is preferably silver. The cermet composite material preferably includes alloy phase portions and a ceramic phase portion. At least part of the ceramic phase portion preferably has a spinel structure.

  1. Inert electrode containing metal oxides, copper and noble metal

    DOE Patents [OSTI]

    Ray, Siba P. (Murrysville, PA); Woods, Robert W. (New Kensington, PA); Dawless, Robert K. (Monroeville, PA); Hosler, Robert B. (Sarver, PA)

    2001-01-01

    A cermet composite material is made by treating at an elevated temperature a mixture comprising a compound of iron and a compound of at least one other metal, together with an alloy or mixture of copper and a noble metal. The alloy or mixture preferably comprises particles having an interior portion containing more copper than noble metal and an exterior portion containing more noble metal than copper. The noble metal is preferably silver. The cermet composite material preferably includes alloy phase portions and a ceramic phase portion. At least part of the ceramic phase portion preferably has a spinel structure.

  2. Aerosol chemical vapor deposition of metal oxide films

    DOE Patents [OSTI]

    Ott, Kevin C. (4745 Trinity Dr., Los Alamos, NM 87544); Kodas, Toivo T. (5200 Noreen Dr. NE., Albuquerque, NM 87111)

    1994-01-01

    A process of preparing a film of a multicomponent metal oxide including: forming an aerosol from a solution comprised of a suitable solvent and at least two precursor compounds capable of volatilizing at temperatures lower than the decomposition temperature of said precursor compounds; passing said aerosol in combination with a suitable oxygen-containing carrier gas into a heated zone, said heated zone having a temperature sufficient to evaporate the solvent and volatilize said precursor compounds; and passing said volatilized precursor compounds against the surface of a substrate, said substrate having a sufficient temperature to decompose said volatilized precursor compounds whereby metal atoms contained within said volatilized precursor compounds are deposited as a metal oxide film upon the substrate is disclosed. In addition, a coated article comprising a multicomponent metal oxide film conforming to the surface of a substrate selected from the group consisting of silicon, magnesium oxide, yttrium-stabilized zirconium oxide, sapphire, or lanthanum gallate, said multicomponent metal oxide film characterized as having a substantially uniform thickness upon said FIELD OF THE INVENTION The present invention relates to the field of film coating deposition techniques, and more particularly to the deposition of multicomponent metal oxide films by aerosol chemical vapor deposition. This invention is the result of a contract with the Department of Energy (Contract No. W-7405-ENG-36).

  3. Method of physical vapor deposition of metal oxides on semiconductors

    DOE Patents [OSTI]

    Norton, David P. (Knoxville, TN)

    2001-01-01

    A process for growing a metal oxide thin film upon a semiconductor surface with a physical vapor deposition technique in a high-vacuum environment and a structure formed with the process involves the steps of heating the semiconductor surface and introducing hydrogen gas into the high-vacuum environment to develop conditions at the semiconductor surface which are favorable for growing the desired metal oxide upon the semiconductor surface yet is unfavorable for the formation of any native oxides upon the semiconductor. More specifically, the temperature of the semiconductor surface and the ratio of hydrogen partial pressure to water pressure within the vacuum environment are high enough to render the formation of native oxides on the semiconductor surface thermodynamically unstable yet are not so high that the formation of the desired metal oxide on the semiconductor surface is thermodynamically unstable. Having established these conditions, constituent atoms of the metal oxide to be deposited upon the semiconductor surface are directed toward the surface of the semiconductor by a physical vapor deposition technique so that the atoms come to rest upon the semiconductor surface as a thin film of metal oxide with no native oxide at the semiconductor surface/thin film interface. An example of a structure formed by this method includes an epitaxial thin film of (001)-oriented CeO.sub.2 overlying a substrate of (001) Ge.

  4. Displacement method and apparatus for reducing passivated metal powders and metal oxides

    DOE Patents [OSTI]

    Morrell; Jonathan S. (Knoxville, TN), Ripley; Edward B. (Knoxville, TN)

    2009-05-05

    A method of reducing target metal oxides and passivated metals to their metallic state. A reduction reaction is used, often combined with a flux agent to enhance separation of the reaction products. Thermal energy in the form of conventional furnace, infrared, or microwave heating may be applied in combination with the reduction reaction.

  5. Plutonium metal and oxide container weld development and qualification

    SciTech Connect (OSTI)

    Fernandez, R.; Horrell, D.R.; Hoth, C.W.; Pierce, S.W.; Rink, N.A.; Rivera, Y.M.; Sandoval, V.D.

    1996-01-01

    Welds were qualified for a container system to be used for long-term storage of plutonium metal and oxide. Inner and outer containers are formed of standard tubing with stamped end pieces gas-tungsten-arc (GTA) welded onto both ends. The weld qualification identified GTA parameters to produce a robust weld that meets the requirements of the Department of Energy standard DOE-STD-3013-94, ``Criteria for the Safe Storage of Plutonium Metals and Oxides.``

  6. Advanced Metal-Oxide based SCR Catalysts | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Metal-Oxide based SCR Catalysts Advanced Metal-Oxide based SCR Catalysts SCR with ammonia as reductant is an effective strategy being utilized to reduce NOx emissions to meet regulated levels. PDF icon deer10_adelmann.pdf More Documents & Publications Hydrocarbon fouling of SCR during Premixed Charge Compression Ignition (PCCI) combustion Catalyst Design for Urea-less Passive Ammonia SCR Lean-Burn SIDI Aftertreatment System Looking From A Hilltop: Automotive Propulsion System Technology

  7. Monolithic Metal Oxide based Composite Nanowire Lean NOx Emission Control

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Catalysts | Department of Energy Monolithic Metal Oxide based Composite Nanowire Lean NOx Emission Control Catalysts Monolithic Metal Oxide based Composite Nanowire Lean NOx Emission Control Catalysts Presents latest progress in the development of a new type of lean NOx trapping catalyst based on heterogenous composite nanowires, which could potentially be used in gasoline and diesel engines. PDF icon deer11_gao.pdf More Documents & Publications Three-Dimensional Composite Nanostructures

  8. Metal Oxide Semiconductor Nanoparticles Open the Door to New Medical

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Innovations | Argonne National Laboratory Metal Oxide Semiconductor Nanoparticles Open the Door to New Medical Innovations Technology available for licensing: novel nanometer-sized metal oxide semiconductors that allow targeting, initiating and control of in vitro and in vivo chemical reactions in biological molecules, such as DNA, proteins, and antibodies. Allows for targeting, initiation and control of in vitro and in vivo chemical reactions in biological molecules Commercial applications

  9. Transition-metal doped sulfide, selenide, and telluride laser crystal and lasers

    DOE Patents [OSTI]

    Krupke, W.F.; Page, R.H.; DeLoach, L.D.; Payne, S.A.

    1996-07-30

    A new class of solid state laser crystals and lasers are formed of transition metal doped sulfide, selenide, and telluride host crystals which have four fold coordinated substitutional sites. The host crystals include II-VI compounds. The host crystal is doped with a transition metal laser ion, e.g., chromium, cobalt or iron. In particular, Cr{sup 2+}-doped ZnS and ZnSe generate laser action near 2.3 {micro}m. Oxide, chloride, fluoride, bromide and iodide crystals with similar structures can also be used. Important aspects of these laser materials are the tetrahedral site symmetry of the host crystal, low excited state absorption losses and high luminescence efficiency, and the d{sup 4} and d{sup 6} electronic configurations of the transition metal ions. The same materials are also useful as saturable absorbers for passive Q-switching applications. The laser materials can be used as gain media in amplifiers and oscillators; these gain media can be incorporated into waveguides and semiconductor lasers. 18 figs.

  10. Transition-metal doped sulfide, selenide, and telluride laser crystal and lasers

    DOE Patents [OSTI]

    Krupke, William F.; Page, Ralph H.; DeLoach, Laura D.; Payne, Stephen A.

    1996-01-01

    A new class of solid state laser crystals and lasers are formed of transition metal doped sulfide, selenide, and telluride host crystals which have four fold coordinated substitutional sites. The host crystals include II-VI compounds. The host crystal is doped with a transition metal laser ion, e.g., chromium, cobalt or iron. In particular, Cr.sup.2+ -doped ZnS and ZnSe generate laser action near 2.3 .mu.m. Oxide, chloride, fluoride, bromide and iodide crystals with similar structures can also be used. Important aspects of these laser materials are the tetrahedral site symmetry of the host crystal, low excited state absorption losses and high luminescence efficiency, and the d.sup.4 and d.sup.6 electronic configurations of the transition metal ions. The same materials are also useful as saturable absorbers for passive Q-switching applications. The laser materials can be used as gain media in amplifiers and oscillators; these gain media can be incorporated into waveguides and semiconductor lasers.

  11. Method of CO and/or CO.sub.2 hydrogenation using doped mixed-metal oxides

    DOE Patents [OSTI]

    Shekhawat, Dushyant; Berry, David A.; Haynes, Daniel J.; Abdelsayed, Victor; Smith, Mark W.; Spivey, James J.

    2015-10-06

    A method of hydrogenation utilizing a reactant gas mixture comprising a carbon oxide and a hydrogen agent, and a hydrogenation catalyst comprising a mixed-metal oxide containing metal sites supported and/or incorporated into the lattice. The mixed-metal oxide comprises a perovskite, a pyrochlore, a fluorite, a brownmillerite, or mixtures thereof doped at the A-site or the B-site. The metal site may comprise a deposited metal, where the deposited metal is a transition metal, an alkali metal, an alkaline earth metal, or mixtures thereof. Contact between the carbon oxide, hydrogen agent, and hydrogenation catalyst under appropriate conditions of temperature, pressure and gas flow rate generate a hydrogenation reaction and produce a hydrogenated product made up of carbon from the carbon oxide and some portion of the hydrogen agent. The carbon oxide may be CO, CO.sub.2, or mixtures thereof and the hydrogen agent may be H.sub.2. In a particular embodiment, the hydrogenated product comprises an alcohol, an olefin, an aldehyde, a ketone, an ester, an oxo-product, or mixtures thereof.

  12. Enhancing conductivity of metallic carbon nanotube networks by transition metal adsorption

    SciTech Connect (OSTI)

    Ketolainen, T. Havu, V.; Puska, M. J.

    2015-02-07

    The conductivity of carbon nanotube thin films is mainly determined by carbon nanotube junctions, the resistance of which can be reduced by several different methods. We investigate electronic transport through carbon nanotube junctions in a four-terminal configuration, where two metallic single-wall carbon nanotubes are linked by a group 6 transition metal atom. The transport calculations are based on the Greens function method combined with the density-functional theory. The transition metal atom is found to enhance the transport through the junction near the Fermi level. However, the size of the nanotube affects the improvement in the conductivity. The enhancement is related to the hybridization of chromium and carbon atom orbitals, which is clearly reflected in the character of eigenstates near the Fermi level. The effects of chromium atoms and precursor molecules remaining adsorbed on the nanotubes outside the junctions are also examined.

  13. Metal-oxide-based energetic materials and synthesis thereof

    DOE Patents [OSTI]

    Tillotson, Thomas M. (Tracy, CA), Simpson; Randall L. (Livermore, CA); Hrubesh, Lawrence W. (Pleasanton, CA)

    2006-01-17

    A method of preparing energetic metal-oxide-based energetic materials using sol-gel chemistry has been invented. The wet chemical sol-gel processing provides an improvement in both safety and performance. Essentially, a metal-oxide oxidizer skeletal structure is prepared from hydrolyzable metals (metal salts or metal alkoxides) with fuel added to the sol prior to gelation or synthesized within the porosity metal-oxide gel matrix. With metal salt precursors a proton scavenger is used to destabilize the sol and induce gelation. With metal alkoxide precursors standard well-known sol-gel hydrolysis and condensation reactions are used. Drying is done by standard sol-gel practices, either by a slow evaporation of the liquid residing within the pores to produce a high density solid nanocomposite, or by supercritical extraction to produce a lower density, high porous nanocomposite. Other ingredients may be added to this basic nanostructure to change physical and chemical properties, which include organic constituents for binders or gas generators during reactions, burn rate modifiers, or spectral emitters.

  14. Catalytic graphitization of carbon aerogels by transition metals

    SciTech Connect (OSTI)

    Maldonado-Hodar, F.J.; Moreno-Castilla, C.; Rivera-Utrilla, J.; Hanzawa, Y.; Yamada, Y.

    2000-05-02

    Carbon aerogels and Cr-, Fe-, Co-, and Ni-containing carbon aerogels were obtained by pyrolysis, at temperatures between 500 and 1,800 C, of the corresponding aerogels prepared by the sol-gel method from polymerization of resorcinol with formaldehyde. All samples were characterized by mercury porosimetry, nitrogen adsorption, X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), and Raman spectroscopy. Results obtained show that carbon aerogels are, essentially, macroporous materials that maintain large pore volumes even after pyrolysis at 1,800 C. For pyrolysis at temperatures higher than 1,000 C, the presence of the transition metals produced graphitized areas with three-dimensional stacking order, as shown by HRTEM, XRD, and Raman spectroscopy. HRTEM also showed that the metal-carbon containing aerogels were formed by polyhedral structures. Cr and Fe seem to be the best catalysts for graphitization of carbon aerogels.

  15. Rare earth-transition metal scrap treatment method

    DOE Patents [OSTI]

    Schmidt, F.A.; Peterson, D.T.; Wheelock, J.T.; Jones, L.L.; Lincoln, L.P.

    1992-02-11

    Rare earth-transition metal (e.g. iron) scrap (e.g. Nd-Fe-B scrap) is melted to reduce the levels of tramp oxygen and nitrogen impurities therein. The tramp impurities are reduced in the melt by virtue of the reaction of the tramp impurities and the rare earth to form dross on the melt. The purified melt is separated from the dross for reuse. The oxygen and nitrogen of the melt are reduced to levels acceptable for reuse of the treated alloy in the manufacture of end-use articles, such as permanent magnets. 3 figs.

  16. Rare earth-transition metal scrap treatment method

    DOE Patents [OSTI]

    Schmidt, Frederick A. (Ames, IA); Peterson, David T. (Ames, IA); Wheelock, John T. (Nevada, IA); Jones, Lawrence L. (Des Moines, IA); Lincoln, Lanny P. (Woodward, IA)

    1992-02-11

    Rare earth-transition metal (e.g. iron) scrap (e.g. Nd-Fe-B scrap) is melted to reduce the levels of tramp oxygen and nitrogen impurities therein. The tramp impurities are reduced in the melt by virtue of the reaction of the tramp impurities and the rare earth to form dross on the melt. The purified melt is separated from the dross for reuse. The oxygen and nitrogen of the melt are reduced to levels acceptable for reuse of the treated alloy in the manufacture of end-use articles, such as permanent magnets.

  17. Cross-plane thermal properties of transition metal dichalcogenides

    SciTech Connect (OSTI)

    Muratore, C.; Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio 45433 ; Varshney, V.; Universal Technology Corporation, Dayton, Ohio 45432 ; Gengler, J. J.; Spectral Energies LLC, Dayton, Ohio 45431 ; Hu, J. J.; Bultman, J. E.; University of Dayton Research Institute, Dayton, Ohio 45469 ; Smith, T. M.; Shamberger, P. J.; Roy, A. K.; Voevodin, A. A.; Qiu, B.; Ruan, X.

    2013-02-25

    In this work, we explore the thermal properties of hexagonal transition metal dichalcogenide compounds with different average atomic masses but equivalent microstructures. Thermal conductivity values of sputtered thin films were compared to bulk crystals. The comparison revealed a >10 fold reduction in thin film thermal conductivity. Structural analysis of the films revealed a turbostratic structure with domain sizes on the order of 5-10 nm. Estimates of phonon scattering lengths at domain boundaries based on computationally derived group velocities were consistent with the observed film microstructure, and accounted for the reduction in thermal conductivity compared to values for bulk crystals.

  18. Correlated electron pseudopotentials for 3d-transition metals

    SciTech Connect (OSTI)

    Trail, J. R. Needs, R. J.

    2015-02-14

    A recently published correlated electron pseudopotentials (CEPPs) method has been adapted for application to the 3d-transition metals, and to include relativistic effects. New CEPPs are reported for the atoms Sc ? Fe, constructed from atomic quantum chemical calculations that include an accurate description of correlated electrons. Dissociation energies, molecular geometries, and zero-point vibrational energies of small molecules are compared with all electron results, with all quantities evaluated using coupled cluster singles doubles and triples calculations. The CEPPs give better results in the correlated-electron calculations than Hartree-Fock-based pseudopotentials available in the literature.

  19. Interactions of Hydrogen Isotopes and Oxides with Metal Tubes

    SciTech Connect (OSTI)

    Glen R. Longhurst

    2008-08-01

    Understanding and accounting for interaction of hydrogen isotopes and their oxides with metal surfaces is important for persons working with tritium systems. Reported data from several investigators have shown that the processes of oxidation, adsorption, absorption, and permeation are all coupled and interactive. A computer model has been developed for predicting the interaction of hydrogen isotopes and their corresponding oxides in a flowing carrier gas stream with the walls of a metallic tube, particularly at low hydrogen concentrations. An experiment has been constructed to validate the predictive model. Predictions from modeling lead to unexpected experiment results.

  20. Synthesis of metal silicide at metal/silicon oxide interface...

    Office of Scientific and Technical Information (OSTI)

    A platinum silicide, -Ptsub 2Si, was successfully formed at the platinumsilicon oxide interface under 25-200 keV electron irradiation. This is of interest since any platinum ...

  1. Ethanol oxidation on metal oxide-supported platinum catalysts

    SciTech Connect (OSTI)

    L. M. Petkovic 090468; Sergey N. Rashkeev; D. M. Ginosar

    2009-09-01

    Ethanol is a renewable fuel that can be used as an additive to gasoline (or its substitute) with the advantage of octane enhancement and reduced carbon monoxide exhaust emissions. However, on Ethanol is a renewable fuel that can be used as an additive to gasoline (or its substitute) with the advantage of octane enhancement and reduced carbon monoxide exhaust emissions. However, on the standard three-way catalysts, the conversion of unburned ethanol is low because both ethanol and some of its partially oxidized derivatives are highly resistant to oxidation. A combination of first-principles density-functional theory (DFT) based calculations and in-situ diffuse reflectance infrared spectroscopy (DRIFTS) analysis was applied to uncover some of the fundamental phenomena associated with ethanol oxidation on Pt containing catalysts. In particular, the objective was to analyze the role of the oxide (i.e., ?-Al2O3 or SiO2) substrate on the ethanol oxidation activity. The results showed that Pt nanoparticles trap and accumulate oxygen at their surface and perimeter sites and play the role of stoves that burn ethanol molecules and their partially oxidized derivatives to the final products. The ?-Al2O3 surfaces provided higher mobility of the fragments of ethanol molecules than the SiO2 surface and hence increased the supply rate of these objects to the Pt particles. This will in turn produce a higher conversion rate of unburned ethanol.and some of its partially oxidized derivatives are highly resistant to oxidation. A combination of first-principles density-functional theory (DFT) based calculations and in-situ diffuse reflectance infrared spectroscopy (DRIFTS) analysis was applied to uncover some of the fundamental phenomena associated with ethanol oxidation on Pt containing catalysts. In particular, the objective was to analyze the role of the oxide (i.e., ?-Al2O3 or SiO2) substrate on the ethanol oxidation activity. The results showed that Pt nanoparticles trap and accumulate oxygen at their surface and perimeter sites and play the role of stoves that burn ethanol molecules and their partially oxidized derivatives to the final products. The ?-Al2O3 surfaces provided higher mobility of the fragments of ethanol molecules than the SiO2 surface and hence increased the supply rate of these objects to the Pt particles. This will in turn produce a higher conversion rate of unburned ethanol.

  2. Methods of making metal oxide nanostructures and methods of controlling morphology of same

    DOE Patents [OSTI]

    Wong, Stanislaus S; Hongjun, Zhou

    2012-11-27

    The present invention includes a method of producing a crystalline metal oxide nanostructure. The method comprises providing a metal salt solution and providing a basic solution; placing a porous membrane between the metal salt solution and the basic solution, wherein metal cations of the metal salt solution and hydroxide ions of the basic solution react, thereby producing a crystalline metal oxide nanostructure.

  3. Vehicle Technologies Office Merit Review 2015: Metal Oxide Nano-Array

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Catalysts for Low Temperature Diesel Oxidation | Department of Energy Metal Oxide Nano-Array Catalysts for Low Temperature Diesel Oxidation Vehicle Technologies Office Merit Review 2015: Metal Oxide Nano-Array Catalysts for Low Temperature Diesel Oxidation Presentation given by U. Conn at 2015 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about metal oxide nano-array catalysts for low temperature diesel oxidation. PDF icon

  4. Metal current collect protected by oxide film

    DOE Patents [OSTI]

    Jacobson, Craig P. (Lafayette, CA); Visco, Steven J. (Berkeley, CA); DeJonghe, Lutgard C. (Lafayette, CA)

    2004-05-25

    Provided are low-cost, mechanically strong, highly electronically conductive current collects and associated structures for solid-state electrochemical devices, techniques for forming these structures, and devices incorporating the structures. The invention provides solid state electrochemical devices having as current interconnects a ferritic steel felt or screen coated with a protective oxide film.

  5. CO2 Induced Phase Transitions in Diamine-Appended Metal-Organic...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    CO2 Induced Phase Transitions in Diamine-Appended Metal-Organic Frameworks Previous Next List Vlaisavljevich, Bess; Odoh, Samuel O.; Schnell, Sondre K.; Dzubak, Allison; Lee,...

  6. Method for continuous synthesis of metal oxide powders

    DOE Patents [OSTI]

    Berry, David A.; Haynes, Daniel J.; Shekhawat, Dushyant; Smith, Mark W.

    2015-09-08

    A method for the rapid and continuous production of crystalline mixed-metal oxides from a precursor solution comprised of a polymerizing agent, chelated metal ions, and a solvent. The method discharges solution droplets of less than 500 .mu.m diameter using an atomizing or spray-type process into a reactor having multiple temperature zones. Rapid evaporation occurs in a first zone, followed by mixed-metal organic foam formation in a second zone, followed by amorphous and partially crystalline oxide precursor formation in a third zone, followed by formation of the substantially crystalline mixed-metal oxide in a fourth zone. The method operates in a continuous rather than batch manner and the use of small droplets as the starting material for the temperature-based process allows relatively high temperature processing. In a particular embodiment, the first zone operates at 100-300.degree. C., the second zone operates at 300-700.degree. C., and the third operates at 700-1000.degree. C., and fourth zone operates at at least 700.degree. C. The resulting crystalline mixed-metal oxides display a high degree of crystallinity and sphericity with typical diameters on the order of 50 .mu.m or less.

  7. Proximity-induced magnetism in transition-metal substituted graphene

    SciTech Connect (OSTI)

    Crook, Charles B.; Constantin, Costel; Ahmed, Towfiq; Zhu, Jian -Xin; Balatsky, Alexander V.; Haraldsen, Jason T.

    2015-08-03

    We investigate the interactions between two identical magnetic impurities substituted into a graphene superlattice. Using a first-principles approach, we calculate the electronic and magnetic properties for transition-metal substituted graphene systems with varying spatial separation. These calculations are compared for three different magnetic impurities, manganese, chromium, and vanadium. We determine the electronic band structure, density of states, and Millikan populations (magnetic moment) for each atom, as well as calculate the exchange parameter between the two magnetic atoms as a function of spatial separation. We find that the presence of magnetic impurities establishes a distinct magnetic moment in the graphene lattice, where the interactions are highly dependent on the spatial and magnetic characteristic between the magnetic and carbon atoms, which leads to either ferromagnetic or antiferromagnetic behavior. Furthermore, through an analysis of the calculated exchange energies and partial density of states, it is determined that interactions between the magnetic atoms can be classified as an RKKY interaction.

  8. Spin and pseudospins in layered transition metal dichalcogenides

    SciTech Connect (OSTI)

    Xu, Xiaodong; Yao, Wang; Xiao, Di; Heinz, Tony F.

    2014-01-01

    The recent emergence of two-dimensional layered materials in particular the transition metal dichalcogenides provides a new laboratory for exploring the internal quantum degrees of freedom of electrons and their potential for new electronics. These degrees of freedom are the real electron spin, the layer pseudospin, and the valley pseudospin. New methods for the quantum control of the spin and these pseudospins arise from the existence of Berry phase-related physical properties and strong spin orbit coupling. The former leads to the versatile control of the valley pseudospin, whereas the latter gives rise to an interplay between the spin and the pseudospins. Here, we provide a brief review of both theoretical and experimental advances in this field.

  9. Ternary alkali-metal and transition metal or metalloid acetylides as alkali-metal intercalation electrodes for batteries

    DOE Patents [OSTI]

    Nemeth, Karoly; Srajer, George; Harkay, Katherine C; Terdik, Joseph Z

    2015-02-10

    Novel intercalation electrode materials including ternary acetylides of chemical formula: A.sub.nMC.sub.2 where A is alkali or alkaline-earth element; M is transition metal or metalloid element; C.sub.2 is reference to the acetylide ion; n is an integer that is 0, 1, 2, 3 or 4 when A is alkali element and 0, 1, or 2 when A is alkaline-earth element. The alkali elements are Lithium (Li), Sodium (Na), Potassium (K), Rubidium (Rb), Cesium (Cs) and Francium (Fr). The alkaline-earth elements are Berilium (Be), Magnesium (Mg), Calcium (Ca), Strontium (Sr), Barium (Ba), and Radium (Ra). M is a transition metal that is any element in groups 3 through 12 inclusive on the Periodic Table of Elements (elements 21 (Sc) to element 30 (Zn)). In another exemplary embodiment, M is a metalloid element.

  10. All-alkoxide synthesis of strontium-containing metal oxides

    DOE Patents [OSTI]

    Boyle, Timothy J. (Albuquerque, NM)

    2001-01-01

    A method for making strontium-containing metal-oxide ceramic thin films from a precursor liquid by mixing a strontium neo-pentoxide dissolved in an amine solvent and at least one metal alkoxide dissolved in a solvent, said at least one metal alkoxide selected from the group consisting of alkoxides of calcium, barium, bismuth, cadmium, lead, titanium, tantalum, hafnium, tungsten, niobium, zirconium, yttrium, lanthanum, antimony, chromium and thallium, depositing a thin film of the precursor liquid on a substrate, and heating the thin film in the presence of oxygen at between 550 and 700.degree. C.

  11. Lithium metal oxide electrodes for lithium cells and batteries

    DOE Patents [OSTI]

    Thackeray, Michael M.; Johnson, Christopher S.; Amine, Khalil; Kim, Jaekook

    2006-11-14

    A lithium metal oxide positive electrode for a non-aqueous lithium cell is disclosed. The cell is prepared in its initial discharged state and has a general formula xLiMO.sub.2.(1-x)Li.sub.2M'O.sub.3 in which 0oxidation state and with at least one ion being Ni, and where M' is one or more ions with an average tetravalent oxidation state. Complete cells or batteries are disclosed with anode, cathode and electrolyte as are batteries of several cells connected in parallel or series or both.

  12. Amorphous semiconducting and conducting transparent metal oxide thin films and production thereof

    DOE Patents [OSTI]

    Perkins, John (Boulder, CO); Van Hest, Marinus Franciscus Antonius Maria (Lakewood, CO); Ginley, David (Evergreen, CO); Taylor, Matthew (Golden, CO); Neuman, George A. (Holland, MI); Luten, Henry A. (Holland, MI); Forgette, Jeffrey A. (Hudsonville, MI); Anderson, John S. (Holland, MI)

    2010-07-13

    Metal oxide thin films and production thereof are disclosed. An exemplary method of producing a metal oxide thin film may comprise introducing at least two metallic elements and oxygen into a process chamber to form a metal oxide. The method may also comprise depositing the metal oxide on a substrate in the process chamber. The method may also comprise simultaneously controlling a ratio of the at least two metallic elements and a stoichiometry of the oxygen during deposition. Exemplary amorphous metal oxide thin films produced according to the methods herein may exhibit highly transparent properties, highly conductive properties, and/or other opto-electronic properties.

  13. Control of cerium oxidation state through metal complex secondary structures

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Levin, Jessica R.; Dorfner, Walter L.; Carroll, Patrick J.; Schelter, Eric J.

    2015-08-11

    A series of alkali metal cerium diphenylhydrazido complexes, Mx(py)y[Ce(PhNNPh)4], M = Li, Na, and K, x = 4 (Li and Na) or 5 (K), and y = 4 (Li), 8 (Na), or 7 (K), were synthesized to probe how a secondary coordination sphere would modulate electronic structures at a cerium cation. The resulting electronic structures of the heterobimetallic cerium diphenylhydrazido complexes were found to be strongly dependent on the identity of the alkali metal cations. When M = Li+ or Na+, the cerium(III) starting material was oxidized with concomitant reduction of 1,2-diphenylhydrazine to aniline. Reduction of 1,2-diphenylhydrazine was not observedmore » when M = K+, and the complex remained in the cerium(III) oxidation state. Oxidation of the cerium(III) diphenylhydrazido complex to the Ce(IV) diphenylhydrazido one was achieved through a simple cation exchange reaction of the alkali metals. As a result, UV-Vis spectroscopy, FTIR spectroscopy, electrochemistry, magnetic susceptibility, and DFT studies were used to probe the oxidation state and the electronic changes that occurred at the metal centre.« less

  14. Oxidation resistant filler metals for direct brazing of structural ceramics

    DOE Patents [OSTI]

    Moorhead, Arthur J. (Knoxville, TN)

    1986-01-01

    A method of joining ceramics and metals to themselves and to one another is described using essentially pure trinickel aluminide and trinickel aluminide containing small amounts of carbon. This method produces strong joints that can withstand high service temperatures and oxidizing environments.

  15. Volatile organometallic complexes suitable for use in chemical vapor depositions on metal oxide films

    DOE Patents [OSTI]

    Giolando, Dean M.

    2003-09-30

    Novel ligated compounds of tin, titanium, and zinc are useful as metal oxide CVD precursor compounds without the detriments of extreme reactivity yet maintaining the ability to produce high quality metal oxide coating by contact with heated substrates.

  16. Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2 Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2 Print Wednesday, 28 September 2005 00:00 The grand goal motivating femtosecond studies of condensed-matter dynamics is to directly measure the structural pathways that connect different crystallographic, electronic, and magnetic phases of solids, as well as the short-lived transition states between reactants and products in chemical and biochemical reactions.

  17. Magnetic ground state of semiconducting transition metal trichalcogenide monolayers

    SciTech Connect (OSTI)

    Sivadas, Mr. Nikhil; Daniels, Matthew W.; Swendsen, Robert H.; Okamoto, Satoshi; Xiao, Di

    2015-01-01

    Layered transition-metal trichalcogenides with the chemical formula ABX3 have attracted recent interest as potential candidates for two-dimensional magnets. Using first-principles calculations within density functional theory, we investigate the magnetic ground states of monolayers of Mn- and Cr-based semiconducting trichalcogenides.We show that the second and third nearest-neighbor exchange interactions (J2 and J3) between magnetic ions, which have been largely overlooked in previous theoretical studies, are crucial in determining the magnetic ground state. Specifically, we find that monolayer CrSiTe3 is an antiferromagnet with a zigzag spin texture due to significant contribution from J3, whereas CrGeTe3 is a ferromagnet with a Curie temperature of 106 K. Monolayers of Mn compounds (MnPS3 and MnPSe3) always show antiferromagnetic N eel order. We identify the physical origin of various exchange interactions, and demonstrate that strain can be an effective knob for tuning the magnetic properties. Possible magnetic ordering in the bulk is also discussed. Our study suggests that ABX3 can be a promising platform to explore two-dimensional magnetic phenomena.

  18. Induce magnetism into silicene by embedding transition-metal atoms

    SciTech Connect (OSTI)

    Sun, Xiaotian; Wang, Lu E-mail: yyli@suda.edu.cn; Lin, Haiping; Hou, Tingjun; Li, Youyong E-mail: yyli@suda.edu.cn

    2015-06-01

    Embedding transition-metal (TM) atoms into nonmagnetic nanomaterials is an efficient way to induce magnetism. Using first-principles calculations, we systematically investigated the structural stability and magnetic properties of TM atoms from Sc to Zn embedded into silicene with single vacancy (SV) and double vacancies (DV). The binding energies for different TM atoms correlate with the TM d-shell electrons. Sc, Ti, and Co show the largest binding energies of as high as 6 eV, while Zn has the lowest binding energy of about 2 eV. The magnetic moment of silicene can be modulated by embedding TM atoms from V to Co, which mainly comes from the 3d orbitals of TM along with partly contributions from the neighboring Si atoms. Fe atom on SV and Mn atom on DV have the largest magnetic moment of more than 3 μB. In addition, we find that doping of N or C atoms on the vacancy site could greatly enhance the magnetism of the systems. Our results provide a promising approach to design silicene-based nanoelectronics and spintronics device.

  19. Proximity-induced magnetism in transition-metal substituted graphene

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Crook, Charles B.; Constantin, Costel; Ahmed, Towfiq; Zhu, Jian -Xin; Balatsky, Alexander V.; Haraldsen, Jason T.

    2015-08-03

    We investigate the interactions between two identical magnetic impurities substituted into a graphene superlattice. Using a first-principles approach, we calculate the electronic and magnetic properties for transition-metal substituted graphene systems with varying spatial separation. These calculations are compared for three different magnetic impurities, manganese, chromium, and vanadium. We determine the electronic band structure, density of states, and Millikan populations (magnetic moment) for each atom, as well as calculate the exchange parameter between the two magnetic atoms as a function of spatial separation. We find that the presence of magnetic impurities establishes a distinct magnetic moment in the graphene lattice, wheremore » the interactions are highly dependent on the spatial and magnetic characteristic between the magnetic and carbon atoms, which leads to either ferromagnetic or antiferromagnetic behavior. Furthermore, through an analysis of the calculated exchange energies and partial density of states, it is determined that interactions between the magnetic atoms can be classified as an RKKY interaction.« less

  20. Influence of uranium hydride oxidation on uranium metal behaviour

    SciTech Connect (OSTI)

    Patel, N.; Hambley, D.; Clarke, S.A.; Simpson, K.

    2013-07-01

    This work addresses concerns that the rapid, exothermic oxidation of active uranium hydride in air could stimulate an exothermic reaction (burning) involving any adjacent uranium metal, so as to increase the potential hazard arising from a hydride reaction. The effect of the thermal reaction of active uranium hydride, especially in contact with uranium metal, does not increase in proportion with hydride mass, particularly when considering large quantities of hydride. Whether uranium metal continues to burn in the long term is a function of the uranium metal and its surroundings. The source of the initial heat input to the uranium, if sufficient to cause ignition, is not important. Sustained burning of uranium requires the rate of heat generation to be sufficient to offset the total rate of heat loss so as to maintain an elevated temperature. For dense uranium, this is very difficult to achieve in naturally occurring circumstances. Areas of the uranium surface can lose heat but not generate heat. Heat can be lost by conduction, through contact with other materials, and by convection and radiation, e.g. from areas where the uranium surface is covered with a layer of oxidised material, such as burned-out hydride or from fuel cladding. These rates of heat loss are highly significant in relation to the rate of heat generation by sustained oxidation of uranium in air. Finite volume modelling has been used to examine the behaviour of a magnesium-clad uranium metal fuel element within a bottle surrounded by other un-bottled fuel elements. In the event that the bottle is breached, suddenly, in air, it can be concluded that the bulk uranium metal oxidation reaction will not reach a self-sustaining level and the mass of uranium oxidised will likely to be small in relation to mass of uranium hydride oxidised. (authors)

  1. Cyclic catalytic upgrading of chemical species using metal oxide materials

    DOE Patents [OSTI]

    White, James H; Schutte, Erick J; Rolfe, Sara L

    2013-05-07

    Processes are disclosure which comprise alternately contacting an oxygen-carrying catalyst with a reducing substance, or a lower partial pressure of an oxidizing gas, and then with the oxidizing gas or a higher partial pressure of the oxidizing gas, whereby the catalyst is alternately reduced and then regenerated to an oxygenated state. In certain embodiments, the oxygen-carrying catalyst comprises at least one metal oxide-containing material containing a composition having the following formulas: (a) Ce.sub.xB.sub.yB'.sub.zB''O.sub..delta., wherein B=Ba, Sr, Ca, or Zr; B'=Mn, Co, and/or Fe; B''=Cu; 0.01metal oxides.

  2. For cermet inert anode containing oxide and metal phases useful for the electrolytic production of metals

    DOE Patents [OSTI]

    Ray, Siba P. (Murrysville, PA); Liu, Xinghua (Monroeville, PA); Weirauch, Douglas A. (Murrysville, PA)

    2002-01-01

    A cermet inert anode for the electrolytic production of metals such as aluminum is disclosed. The inert anode comprises a ceramic phase including an oxide of Ni, Fe and M, where M is at least one metal selected from Zn, Co, Al, Li, Cu, Ti, V, Cr, Zr, Nb, Ta, W, Mo, Hf and rare earths, preferably Zn and/or Co. Preferred ceramic compositions comprise Fe.sub.2 O.sub.3, NiO and ZnO or CoO. The cermet inert anode also comprises a metal phase such as Cu, Ag, Pd, Pt, Au, Rh, Ru, Ir and/or Os. A preferred metal phase comprises Cu and Ag. The cermet inert anodes may be used in electrolytic reduction cells for the production of commercial purity aluminum as well as other metals.

  3. Electrochromic Nickel Oxide Simultaneously Doped with Lithium and a Metal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Dopant - Energy Innovation Portal Advanced Materials Advanced Materials Find More Like This Return to Search Electrochromic Nickel Oxide Simultaneously Doped with Lithium and a Metal Dopant National Renewable Energy Laboratory Contact NREL About This Technology Technology Marketing Summary Certain materials, referred to as electrochromic materials, are known to change their optical properties in response to the application of an electrical potential. This property has been taken advantage of

  4. Metal Oxide Semiconductor Nanoparticles Pave the Way for Medical Innovation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    - Energy Innovation Portal Find More Like This Return to Search Metal Oxide Semiconductor Nanoparticles Pave the Way for Medical Innovation Argonne National Laboratory Contact ANL About This Technology <p> Titanium dioxide nanocomposites &ldquo;locate and destroy&rdquo; defective cell lines using the white light-induced redox chemistry of TiO<sub>2</sub> nanoparticles and recognition properties of biomolecules. When the nanoparticles are linked to oligonucleotides,

  5. Synthesis of metal-metal oxide catalysts and electrocatalysts using a metal cation adsorption/reduction and adatom replacement by more noble ones

    DOE Patents [OSTI]

    Adzic, Radoslav; Vukmirovic, Miomir; Sasaki, Kotaro

    2010-04-27

    The invention relates to platinum-metal oxide composite particles and their use as electrocatalysts in oxygen-reducing cathodes and fuel cells. The invention particularly relates to methods for preventing the oxidation of the platinum electrocatalyst in the cathodes of fuel cells by use of these platinum-metal oxide composite particles. The invention additionally relates to methods for producing electrical energy by supplying such a fuel cell with an oxidant, such as oxygen, and a fuel source, such as hydrogen. The invention also relates to methods of making the metal-metal oxide composites.

  6. Strategies to Suppress Cation Vacancies in Metal Oxide Alloys: Consequences for Solar Energy Conversion

    SciTech Connect (OSTI)

    Toroker, Maytal; Carter, Emily A.

    2015-09-01

    First-row transition metal oxides (TMOs) are promising alternative materials for inexpensive and efficient solar energy conversion. However, their conversion efficiency can be deleteriously affected by material imperfections, such as atomic vacancies. In this work, we provide examples showing that in some iron-containing TMOs, iron cation vacancy formation can be suppressed via alloying. We calculate within density functional theory+U theory the iron vacancy formation energy in binary rock-salt oxide alloys that contain iron, manganese, nickel, zinc, and/or magnesium. We demonstrate that formation of iron vacancies is less favorable if we choose to alloy iron(II) oxide with metals that cannot readily accept vacancy-generated holes, e.g., magnesium, manganese, nickel, or zinc. Since there are less available sites for holes and the holes are forced to reside on iron cations, the driving force for iron vacancy formation decreases. These results are consistent with an experiment observing a sharp drop in cation vacancy concentration upon alloying iron(II) oxide with manganese.

  7. Microalloying of transition metal silicides by mechanical activation and field-activated reaction

    DOE Patents [OSTI]

    Munir, Zuhair A. (Davis, CA); Woolman, Joseph N. (Davis, CA); Petrovic, John J. (Los Alamos, NM)

    2003-09-02

    Alloys of transition metal suicides that contain one or more alloying elements are fabricated by a two-stage process involving mechanical activation as the first stage and densification and field-activated reaction as the second stage. Mechanical activation, preferably performed by high-energy planetary milling, results in the incorporation of atoms of the alloying element(s) into the crystal lattice of the transition metal, while the densification and field-activated reaction, preferably performed by spark plasma sintering, result in the formation of the alloyed transition metal silicide. Among the many advantages of the process are its ability to accommodate materials that are incompatible in other alloying methods.

  8. Phase transition into the metallic state in hypothetical (without molecules) dense atomic hydrogen

    SciTech Connect (OSTI)

    Khomkin, A. L. Shumikhin, A. S.

    2013-10-15

    A simple physical model of the metal-dielectric (vapor-liquid) phase transition in hypothetical (without molecules) atomic hydrogen is proposed. The reason for such a transition is the quantum collective cohesive energy occurring due to quantum electron-electron exchange similar to the cohesive energy in the liquid-metal phase of alkali metals. It is found that the critical parameters of the transition are P{sub c} ? 41000 atm, ?{sub c} ? 0.1 g/cm{sup 3}, and T{sub c} ? 9750 K.

  9. Scaling Relationships for Adsorption Energies of C2 Hydrocarbons on Transition Metal Surfaces

    SciTech Connect (OSTI)

    Jones, G

    2011-08-18

    Using density functional theory calculations we show that the adsorption energies for C{sub 2}H{sub x}-type adsorbates on transition metal surfaces scale with each other according to a simple bond order conservation model. This observation generalizes some recently recognized adsorption energy scaling laws for AH{sub x}-type adsorbates to unsaturated hydrocarbons and establishes a coherent simplified description of saturated as well as unsaturated hydrocarbons adsorbed on transition metal surfaces. A number of potential applications are discussed. We apply the model to the dehydrogenation of ethane over pure transition metal catalysts. Comparison with the corresponding full density functional theory calculations shows excellent agreement.

  10. Strengthening of metallic alloys with nanometer-size oxide dispersions

    DOE Patents [OSTI]

    Flinn, J.E.; Kelly, T.F.

    1999-06-01

    Austenitic stainless steels and nickel-base alloys containing, by wt. %, 0.1 to 3.0% V, 0.01 to 0.08% C, 0.01 to 0.5% N, 0.05% max. each of Al and Ti, and 0.005 to 0.10% O, are strengthened and ductility retained by atomization of a metal melt under cover of an inert gas with added oxygen to form approximately 8 nanometer-size hollow oxides within the alloy grains and, when the alloy is aged, strengthened by precipitation of carbides and nitrides nucleated by the hollow oxides. Added strengthening is achieved by nitrogen solid solution strengthening and by the effect of solid oxides precipitated along and pinning grain boundaries to provide temperature-stabilization and refinement of the alloy grains. 20 figs.

  11. Lithium metal oxide electrodes for lithium cells and batteries

    DOE Patents [OSTI]

    Thackeray, Michael M. (Naperville, IL); Johnson, Christopher S. (Naperville, IL); Amine, Khalil (Oakbrook, IL)

    2008-12-23

    A lithium metal oxide positive electrode for a non-aqueous lithium cell is disclosed. The cell is prepared in its initial discharged state and has a general formula xLiMO.sub.2.(1-x)Li.sub.2M'O.sub.3 in which 0oxidation state and with at least one ion being Mn or Ni, and where M' is one or more ion with an average tetravalent oxidation state. Complete cells or batteries are disclosed with anode, cathode and electrolyte as are batteries of several cells connected in parallel or series or both.

  12. Strengthening of metallic alloys with nanometer-size oxide dispersions

    DOE Patents [OSTI]

    Flinn, John E. (Idaho Falls, ID); Kelly, Thomas F. (Madison, WI)

    1999-01-01

    Austenitic stainless steels and nickel-base alloys containing, by wt. %, 0.1 to 3.0% V, 0.01 to 0.08% C, 0.01 to 0.5% N, 0.05% max. each of Al and Ti, and 0.005 to 0.10% O, are strengthened and ductility retained by atomization of a metal melt under cover of an inert gas with added oxygen to form approximately 8 nanometer-size hollow oxides within the alloy grains and, when the alloy is aged, strengthened by precipitation of carbides and nitrides nucleated by the hollow oxides. Added strengthening is achieved by nitrogen solid solution strengthening and by the effect of solid oxides precipitated along and pinning grain boundaries to provide temperature-stabilization and refinement of the alloy grains.

  13. Lithium Metal Oxide Electrodes For Lithium Cells And Batteries

    DOE Patents [OSTI]

    Thackeray, Michael M. (Naperville, IL); Johnson, Christopher S. (Naperville, IL); Amine, Khalil (Downers Grove, IL); Kim, Jaekook (Naperville, IL)

    2004-01-20

    A lithium metal oxide positive electrode for a non-aqueous lithium cell is disclosed. The cell is prepared in its initial discharged state and has a general formula xLiMO.sub.2.(1-x)Li.sub.2 M'O.sub.3 in which 0oxidation state and with at least one ion being Mn or Ni, and where M' is one or more ion with an average tetravalent oxidation state. Complete cells or batteries are disclosed with anode, cathode and electrolyte as are batteries of several cells connected in parallel or series or both.

  14. Properties of molecular beam epitaxy grown Eu{sub x}(transition metal){sub y} films (transition metals: Mn, Cr)

    SciTech Connect (OSTI)

    Balin, K.; Nowak, A.; Gibaud, A.; Szade, J.; Celinski, Z.

    2011-04-01

    The electronic and crystallographic structures, as well as the magnetic properties, of Eu{sub x}(transition metal){sub y} (transition metals: Mn, Cr) thin films grown by molecular beam epitaxy were studied. Relative changes of the Eu/Mn and Eu/Cr ratios derived from the XPS lines, as well as x-ray reflectivity, indicate mixing of the Eu/Mn and Eu/Cr layers. Valency transitions from Eu{sup 2+} to Eu{sup 3+} were observed in both systems for most studied stoichiometries. A transition to a magnetically ordered phase was observed at 15 K, 40 K, and 62 K for selected films in the Eu-Mn system, and at 50 K for the film with a Eu/Cr ratio of 0.5.

  15. Metal/metal oxide doped oxide catalysts having high deNOx selectivity for lean NOx exhaust aftertreatment systems

    DOE Patents [OSTI]

    Park, Paul W.

    2004-03-16

    A lean NOx catalyst and method of preparing the same is disclosed. The lean NOx catalyst includes a ceramic substrate, an oxide support material, preferably .gamma.-alumina, deposited on the substrate and a metal promoter or dopant introduced into the oxide support material. The metal promoters or dopants are selected from the group consisting of indium, gallium, tin, silver, germanium, gold, nickel, cobalt, copper, iron, manganese, molybdenum, chromium, cerium, vanadium, oxides thereof, and combinations thereof. The .gamma.-alumina preferably has a pore volume of from about 0.5 to about 2.0 cc/g; a surface area of between about 80 to 350 m.sup.2 /g; an average pore size diameter of between about 3 to 30 nm; and an impurity level of less than or equal to 0.2 weight percent. In a preferred embodiment the .gamma.-alumina is prepared by a sol-gel method, with the metal doping of the .gamma.-alumina preferably accomplished using an incipient wetness impregnation technique.

  16. The carburization of transition metal molybdates (MxMoO?, M= Cu, Ni or Co) and the generation of highly active metal/carbide catalysts for CO? hydrogenation

    SciTech Connect (OSTI)

    Rodriguez, Jose A.; Xu, Wenqian; Ramirez, Pedro J.; Stachiola, Dario; Brito, Joaquin L.

    2015-05-06

    A new approach has been tested for the preparation of metal/Mo?C catalysts using mixed-metal oxide molybdates as precursors. Synchrotron-based in situ time-resolved X-ray diffraction was used to study the reduction and carburization processes of Cu?(MoO?)?(OH)?, a-NiMoO? and CoMoO?nH?O by thermal treatment under mixtures of hydrogen and methane. In all cases, the final product was ?-Mo?C and a metal phase (Cu, Ni, or Co), but the transition sequence varied with the different metals, and it could be related to the reduction potential of the Cu?, Ni? and Co? cations inside each molybdate. The synthesized Cu/Mo?C, Ni/Mo?C and Co/Mo?C catalysts were highly active for the hydrogenation of CO?. The metal/Mo?C systems exhibited large variations in the selectivity towards methanol, methane and CnH?n?? (n > 2) hydrocarbons depending on the nature of the supported metal and its ability to cleave C-O bonds. Cu/Mo?C displayed a high selectivity for CO and methanol production. Ni/Mo?C and Co/Mo?C were the most active catalysts for the activation and full decomposition of CO?, showing high selectivity for the production of methane (Ni case) and CnH?n?? (n > 2) hydrocarbons (Co case).

  17. Metal/semiconductor phase transition in chromium nitride(001...

    Office of Scientific and Technical Information (OSTI)

    Metalsemiconductor phase transition in chromium nitride(001) grown by rf-plasma-assisted molecular-beam epitaxy Citation Details In-Document Search Title: Metalsemiconductor...

  18. Multilayered thermal insulation formed of zirconia bonded layers of zirconia fibers and metal oxide fibers and method for making same

    DOE Patents [OSTI]

    Wrenn, Jr., George E. (Clinton, TN); Holcombe, Jr., Cressie E. (Farragut, TN)

    1988-01-01

    A multilayered thermal insulating composite is formed of a first layer of zirconia-bonded zirconia fibers for utilization near the hot phase or surface of a furnace or the like. A second layer of zirconia-bonded metal oxide fibers is attached to the zirconia fiber layer by a transition layer formed of intermingled zirconia fibers and metal oxide fibers. The thermal insulation is fabricated by vacuum molding with the layers being sequentially applied from aqueous solutions containing the fibers to a configured mandrel. A portion of the solution containing the fibers forming the first layer is intermixed with the solution containing the fibers of the second layer for forming the layer of mixed fibers. The two layers of fibers joined together by the transition layer are saturated with a solution of zirconium oxynitrate which provides a zirconia matrix for the composite when the fibers are sintered together at their nexi.

  19. Multilayered thermal insulation formed of zirconia bonded layers of zirconia fibers and metal oxide fibers and method for making same

    DOE Patents [OSTI]

    Wrenn, G.E. Jr.; Holcombe, C.E. Jr.

    1988-09-13

    A multilayered thermal insulating composite is formed of a first layer of zirconia-bonded zirconia fibers for utilization near the hot phase or surface of a furnace or the like. A second layer of zirconia-bonded metal oxide fibers is attached to the zirconia fiber layer by a transition layer formed of intermingled zirconia fibers and metal oxide fibers. The thermal insulation is fabricated by vacuum molding with the layers being sequentially applied from aqueous solutions containing the fibers to a configured mandrel. A portion of the solution containing the fibers forming the first layer is intermixed with the solution containing the fibers of the second layer for forming the layer of mixed fibers. The two layers of fibers joined together by the transition layer are saturated with a solution of zirconium oxynitrate which provides a zirconia matrix for the composite when the fibers are sintered together at their nexi.

  20. Quantum confinement in transition metal oxide quantum wells ...

    Office of Scientific and Technical Information (OSTI)

    Department of Physics, The University of Texas at Austin, Austin, Texas 78712 (United States) Department of Physics, New Mexico State University, Las Cruces, New Mexico 88003 ...

  1. Superconductors and Complex Transition Metal Oxides for Tunable...

    Office of Scientific and Technical Information (OSTI)

    Ranjan 1 ; Xiong, Jie 1 ; Azad, Md A. 1 ; Yang, Hao 1 ; Trugman, Stuart A. 1 ; Jia, Quanxi 1 ; Taylor, Antoinette 1 ; Chen, Houtong 1 + Show Author Affiliations Los...

  2. Metal-insulator transition of the reduced surface of yttria-stabilized

    Office of Scientific and Technical Information (OSTI)

    zirconia near Pt electrodes. (Journal Article) | SciTech Connect Journal Article: Metal-insulator transition of the reduced surface of yttria-stabilized zirconia near Pt electrodes. Citation Details In-Document Search Title: Metal-insulator transition of the reduced surface of yttria-stabilized zirconia near Pt electrodes. Abstract not provided. Authors: Siegel, David A ; El Gabaly Marquez, Farid ; McCarty, Kevin F ; Bartelt, Norman Charles. Publication Date: 2014-09-01 OSTI Identifier:

  3. Bridged transition-metal complexes and uses thereof for hydrogen separation, storage and hydrogenation

    DOE Patents [OSTI]

    Lilga, Michael A. (Richland, WA); Hallen, Richard T. (Richland, WA)

    1991-01-01

    The present invention constitutes a class of organometallic complexes which reversibly react with hydrogen to form dihydrides and processes by which these compounds can be utilized. The class includes bimetallic complexes in which two cyclopentadienyl rings are bridged together and also separately .pi.-bonded to two transition metal atoms. The transition metals are believed to bond with the hydrogen in forming the dihydride. Transition metals such as Fe, Mn or Co may be employed in the complexes although Cr constitutes the preferred metal. A multiple number of ancilliary ligands such as CO are bonded to the metal atoms in the complexes. Alkyl groups and the like may be substituted on the cyclopentadienyl rings. These organometallic compounds may be used in absorption/desorption systems and in facilitated transport membrane systems for storing and separating out H.sub.2 from mixed gas streams such as the product gas from coal gasification processes.

  4. Bridged transition-metal complexes and uses thereof for hydrogen separation, storage and hydrogenation

    DOE Patents [OSTI]

    Lilga, Michael A. (Richland, WA); Hallen, Richard T. (Richland, WA)

    1990-01-01

    The present invention constitutes a class of organometallic complexes which reversibly react with hydrogen to form dihydrides and processes by which these compounds can be utilized. The class includes bimetallic complexes in which two cyclopentadienyl rings are bridged together and also separately .pi.-bonded to two transition metal atoms. The transition metals are believed to bond with the hydrogen in forming the dihydride. Transition metals such as Fe, Mn or Co may be employed in the complexes although Cr constitutes the preferred metal. A multiple number of ancilliary ligands such as CO are bonded to the metal atoms in the complexes. Alkyl groups and the like may be substituted on the cyclopentadienyl rings. These organometallic compounds may be used in absorption/desorption systems and in facilitated transport membrane systems for storing and separating out H.sub.2 from mixed gas streams such as the produce gas from coal gasification processes.

  5. Preparation of transition metal nanoparticles and surfaces modified with (co)polymers synthesized by RAFT

    DOE Patents [OSTI]

    McCormick, III, Charles L. (Hattiesburg, MS); Lowe, Andrew B. (Hattiesburg, MS); Sumerlin, Brent S. (Pittsburgh, PA)

    2011-12-27

    A new, facile, general one-phase method of generating thiol-functionalized transition metal nanoparticles and surfaces modified by (co)polymers synthesized by the RAFT method is described. The method includes the steps of forming a (co)polymer in aqueous solution using the RAFT methodology, forming a colloidal transition metal precursor solution from an appropriate transition metal; adding the metal precursor solution or surface to the (co)polymer solution, adding a reducing agent into the solution to reduce the metal colloid in situ to produce the stabilized nanoparticles or surface, and isolating the stabilized nanoparticles or surface in a manner such that aggregation is minimized. The functionalized surfaces generated using these methods can further undergo planar surface modifications, such as functionalization with a variety of different chemical groups, expanding their utility and application.

  6. Preparation of transition metal nanoparticles and surfaces modified with (CO)polymers synthesized by RAFT

    DOE Patents [OSTI]

    McCormick, III., Charles L.; Lowe, Andrew B.; Sumerlin, Brent S.

    2006-11-21

    A new, facile, general one-phase method of generating thio-functionalized transition metal nanoparticles and surfaces modified by (co)polymers synthesized by the RAFT method is described. The method includes the stops of forming a (co)polymer in aqueous solution using the RAFT methodology, forming a colloidal transition metal precursor solution from an appropriate transition metal; adding the metal precursor solution or surface to the (co)polymer solution, adding a reducing agent into the solution to reduce the metal colloid in situ to produce the stabilized nanoparticles or surface, and isolating the stabilized nanoparticles or surface in a manner such that aggregation is minimized. The functionalized surfaces generated using these methods can further undergo planar surface modifications, such as functionalization with a variety of different chemical groups, expanding their utility and application.

  7. Preparation of transition metal nanoparticles and surfaces modified with (CO) polymers synthesized by RAFT

    DOE Patents [OSTI]

    McCormick, III, Charles L. (Hattiesburg, MS); Lowe, Andrew B. (Hattiesburg, MS); Sumerlin, Brent S. (Pittsburgh, PA)

    2006-10-25

    A new, facile, general one-phase method of generating thiol-functionalized transition metal nanoparticles and surface modified by (co)polymers synthesized by the RAFT method is described. The method includes the steps of forming a (co)polymer in aqueous solution using the RAFT methodology, forming a collidal transition metal precursor solution from an appropriate transition metal; adding the metal precursor solution or surface to the (co)polymer solution, adding a reducing agent into the solution to reduce the metal colloid in situ to produce the stabilized nanoparticles or surface, and isolating the stabilized nanoparticles or surface in a manner such that aggregation is minimized. The functionalized surfaces generated using these methods can further undergo planar surface modifications, such as fuctionalization with a variety of different chemical groups, expanding their utility and application.

  8. Bridged transition-metal complexes and uses thereof for hydrogen separation, storage and hydrogenation

    DOE Patents [OSTI]

    Lilga, M.A.; Hallen, R.T.

    1991-10-15

    The present invention constitutes a class of organometallic complexes which reversibly react with hydrogen to form dihydrides and processes by which these compounds can be utilized. The class includes bimetallic complexes in which two cyclopentadienyl rings are bridged together and also separately [pi]-bonded to two transition metal atoms. The transition metals are believed to bond with the hydrogen in forming the dihydride. Transition metals such as Fe, Mn or Co may be employed in the complexes although Cr constitutes the preferred metal. A multiple number of ancillary ligands such as CO are bonded to the metal atoms in the complexes. Alkyl groups and the like may be substituted on the cyclopentadienyl rings. These organometallic compounds may be used in absorption/desorption systems and in facilitated transport membrane systems for storing and separating out H[sub 2] from mixed gas streams such as the product gas from coal gasification processes. 3 figures.

  9. Bridged transition-metal complexes and uses thereof for hydrogen separation, storage and hydrogenation

    DOE Patents [OSTI]

    Lilga, M.A.; Hallen, R.T.

    1990-08-28

    The present invention constitutes a class of organometallic complexes which reversibly react with hydrogen to form dihydrides and processes by which these compounds can be utilized. The class includes bimetallic complexes in which two cyclopentadienyl rings are bridged together and also separately [pi]-bonded to two transition metal atoms. The transition metals are believed to bond with the hydrogen in forming the dihydride. Transition metals such as Fe, Mn or Co may be employed in the complexes although Cr constitutes the preferred metal. A multiple number of ancillary ligands such as CO are bonded to the metal atoms in the complexes. Alkyl groups and the like may be substituted on the cyclopentadienyl rings. These organometallic compounds may be used in absorption/desorption systems and in facilitated transport membrane systems for storing and separating out H[sub 2] from mixed gas streams such as the producer gas from coal gasification processes. 3 figs.

  10. Memristor using a transition metal nitride insulator (Patent...

    Office of Scientific and Technical Information (OSTI)

    at least one resistive switching element is interposed between at least a first and a second conducting electrode element. The resistive switching element comprises a metal...

  11. Magnetic preferential orientation of metal oxide superconducting materials

    DOE Patents [OSTI]

    Capone, D.W.; Dunlap, B.D.; Veal, B.W.

    1990-07-17

    A superconductor comprised of a polycrystalline metal oxide such as YBa[sub 2]Cu[sub 3]O[sub 7[minus]X] (where 0 < X < 0.5) exhibits superconducting properties and is capable of conducting very large current densities. By aligning the two-dimensional Cu-O layers which carry the current in the superconducting state in the a- and b-directions, i.e., within the basal plane, a high degree of crystalline axes alignment is provided between adjacent grains permitting the conduction of high current densities. The highly anisotropic diamagnetic susceptibility of the polycrystalline metal oxide material permits the use of an applied magnetic field to orient the individual crystals when in the superconducting state to substantially increase current transport between adjacent grains. In another embodiment, the anisotropic paramagnetic susceptibility of rare-earth ions substituted into the oxide material is made use of as an applied magnetic field orients the particles in a preferential direction. This latter operation can be performed with the material in the normal (non-superconducting) state. 4 figs.

  12. Magnetic preferential orientation of metal oxide superconducting materials

    DOE Patents [OSTI]

    Capone, Donald W. (Bolingbrook, IL); Dunlap, Bobby D. (Bolingbrook, IL); Veal, Boyd W. (Downers Grove, IL)

    1990-01-01

    A superconductor comprised of a polycrystalline metal oxide such as YBa.sub.2 Cu.sub.3 O.sub.7-X (where 0metal oxide material permits the use of an applied magnetic field to orient the individual crystals when in the superconducting state to substantially increase current transport between adjacent grains. In another embodiment, the anisotropic paramagnetic susceptibility of rare-earth ions substituted into the oxide material is made use of as an applied magnetic field orients the particles in a preferential direction. This latter operation can be performed with the material in the normal (non-superconducting) state.

  13. Non-equilibrium oxidation states of zirconium during early stages of metal oxidation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ma, Wen; Senanayake, Sanjaya D.; Herbert, F. William; Yildiz, Bilge

    2015-03-11

    The chemical state of Zr during the initial, self-limiting stage of oxidation on single crystal zirconium (0001), with oxide thickness on the order of 1 nm, was probed by synchrotron x-ray photoelectron spectroscopy. Quantitative analysis of the Zr 3d spectrum by the spectrum reconstruction method demonstrated the formation of Zr1+, Zr2+, and Zr3+ as non-equilibrium oxidation states, in addition to Zr4+ in the stoichiometric ZrO2. This finding resolves the long-debated question of whether it is possible to form any valence states between Zr0 and Zr4+ at the metal-oxide interface. As a result, the presence of local strong electric fields andmore » the minimization of interfacial energy are assessed and demonstrated as mechanisms that can drive the formation of these non-equilibrium valence states of Zr.« less

  14. Synthesis of metal silicide at metal/silicon oxide interface by electronic excitation

    SciTech Connect (OSTI)

    Lee, J.-G.; Nagase, T.; Yasuda, H.; Mori, H.

    2015-05-21

    The synthesis of metal silicide at the metal/silicon oxide interface by electronic excitation was investigated using transmission electron microscopy. A platinum silicide, ?-Pt{sub 2}Si, was successfully formed at the platinum/silicon oxide interface under 25200?keV electron irradiation. This is of interest since any platinum silicide was not formed at the platinum/silicon oxide interface by simple thermal annealing under no-electron-irradiation conditions. From the electron energy dependence of the cross section for the initiation of the silicide formation, it is clarified that the silicide formation under electron irradiation was not due to a knock-on atom-displacement process, but a process induced by electronic excitation. It is suggested that a mechanism related to the Knotek and Feibelman mechanism may play an important role in silicide formation within the solid. Similar silicide formation was also observed at the palladium/silicon oxide and nickel/silicon oxide interfaces, indicating a wide generality of the silicide formation by electronic excitation.

  15. Electrostatic Cooperativity of Hydroxyl Groups at Metal Oxide Surfaces

    SciTech Connect (OSTI)

    Boily, Jean F.; Lins, Roberto D.

    2009-09-24

    The O-H bond distribution of hydroxyl groups at the {110} goethite (R-FeOOH) surface was investigated by molecular dynamics. This distribution was strongly affected by electrostatic interactions with neighboring oxo and hydroxo groups. The effects of proton surface loading, simulated by emplacing two protons at different distances of separation, were diverse and generated several sets of O-H bond distributions. DFT calculations of a representative molecular cluster were also carried out to demonstrate the impact of these effects on the orientation of oxygen lone pairs in neighboring oxo groups. These effects should have strong repercussions on O-H stretching vibrations of metal oxide surfaces.h

  16. Lithium metal oxide electrodes for lithium cells and batteries

    DOE Patents [OSTI]

    Thackeray, Michael M. (Naperville, IL); Johnson, Christopher S. (Naperville, IL); Amine, Khalil (Downers Grove, IL); Kim, Jaekook (Naperville, IL)

    2004-01-13

    A lithium metal oxide positive electrode for a non-aqueous lithium cell is disclosed. The cell is prepared in its initial discharged state and has a general formula xLiMO.sub.2.(1-x)Li.sub.2 M'O.sub.3 in which 0

  17. Cyclic catalytic upgrading of chemical species using metal oxide materials

    DOE Patents [OSTI]

    White, James H. (Boulder, CO); Schutte, Erick J. (Thornton, CO); Rolfe, Sara L. (Loveland, CO)

    2010-11-02

    Processes are disclosure which comprise alternately contacting an oxygen-carrying catalyst with a reducing substance, or a lower partial pressure of an oxidizing gas, and then with the oxidizing gas or a higher partial pressure of the oxidizing gas, whereby the catalyst is alternately reduced and then regenerated to an oxygenated state. In certain embodiments, the oxygen-carrying catalyst comprises at least one metal oxide-containing material containing a composition having one of the following formulas: (a) Ce.sub.xB.sub.yB'.sub.zB''O.sub..delta., wherein B=Ba, Sr, Ca, or Zr; B'=Mn, Co, or Fe; B''=Cu; 0.01

  18. Monitoring the formation of carbide crystal phases during the thermal decomposition of 3d transition metal dicarboxylate complexes

    SciTech Connect (OSTI)

    Huba, ZJ; Carpenter, EE

    2014-06-06

    Single molecule precursors can help to simplify the synthesis of complex alloys by minimizing the amount of necessary starting reagents. However, single molecule precursors are time consuming to prepare with very few being commercially available. In this study, a simple precipitation method is used to prepare Fe, Co, and Ni fumarate and succinate complexes. These complexes were then thermally decomposed in an inert atmosphere to test their efficiency as single molecule precursors for the formation of metal carbide phases. Elevated temperature X-ray diffraction was used to identify the crystal phases produced upon decomposition of the metal dicarboxylate complexes. Thermogravimetric analysis coupled with an infrared detector was used to identify the developed gaseous decomposition products. All complexes tested showed a reduction from the starting M2+ oxidation state to the M oxidation state, upon decomposition. Also, each complex tested showed CO2 and H2O as gaseous decomposition products. Nickel succinate, iron succinate, and iron fumarate complexes were found to form carbide phases upon decomposition. This proves that transition metal dicarboxylate salts can be employed as efficient single molecule precursors for the formation of metal carbide crystal phases.

  19. Neutral bimetallic transition metal phenoxyiminato catalysts and related polymerization methods

    DOE Patents [OSTI]

    Marks, Tobin J. (Evanston, IL); Rodriguez, Brandon A. (Evanston, IL); Delferro, Massimiliano (Chicago, IL)

    2012-08-07

    A catalyst composition comprising a neutral bimetallic diphenoxydiiminate complex of group 10 metals or Ni, Pd or Pt is disclosed. The compositions can be used for the preparation of homo- and co-polymers of olefinic monomer compounds.

  20. Poly(cyclohexylethylene)-block-poly(ethylene oxide) block polymers for metal oxide templating

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Schulze, Morgan W.; Sinturel, Christophe; Hillmyer, Marc A.

    2015-09-01

    A series of poly(cyclohexylethylene)-block-poly(ethylene oxide) (CEO) diblock copolymers were synthesized through tandem anionic polymerizations and heterogeneous catalytic hydrogenation. Solvent-annealed CEO diblock films were used to template dense arrays of inorganic oxide nanodots via simple spin coating of an inorganic precursor solution atop the ordered film. The substantial chemical dissimilarity of the two blocks enables (i) selective inclusion of the inorganic precursor within the PEO domain and (ii) the formation of exceptionally small feature sizes due to a relatively large interaction parameter estimated from mean-field analysis of the order–disorder transition temperatures of compositionally symmetric samples. UV/ozone treatment following incorporation produces anmore » ordered arrangement of oxide nanodots and simultaneously removes the block polymer template. However, we report the smallest particles (6 ± 1 nm) templated from a selective precursor insertion method to date using a block polymer scaffold.« less

  1. Acoustic plane wave preferential orientation of metal oxide superconducting materials

    DOE Patents [OSTI]

    Tolt, Thomas L. (North Olmsted, OH); Poeppel, Roger B. (Glen Ellyn, IL)

    1991-01-01

    A polycrystalline metal oxide such as YBa.sub.2 Cu.sub.3 O.sub.7-X (where 0metal oxide in the form of a ceramic slip which has not yet set, orientation of the crystal basal planes parallel with the direction of desired current flow is accomplished by an applied acoustic plane wave in the acoustic or ultrasonic frequency range (either progressive or standing) in applying a torque to each crystal particle. The ceramic slip is then set and fired by conventional methods to produce a conductor with preferentially oriented grains and substantially enhanced current carrying capacity.

  2. Preferential orientation of metal oxide superconducting materials by mechanical means

    DOE Patents [OSTI]

    Capone, Donald W. (Bolingbrook, IL)

    1990-01-01

    A superconductor comprised of a polycrystalline metal oxide such as YBa.sub.2 Cu.sub.3 O.sub.7-X (where 0<.times.<0.5) is capable of accommodating very large current densities. By aligning the two-dimensional Cu--O layers which carry the current in the superconducting state in the a- and b-directions, i.e., within the basal plane, a high degree of crystalline axes alignment is provided between adjacent grains permitting the metal oxide material to accommodate high current densities. The orthorhombic crystalline particles have a tendency to lie down on one of the longer sides, i.e., on the a- or b-direction. Aligning the crystals in this orientation is accomplished by mechanical working of the material such as by extrusion, tape casting or slip casting, provided a single crystal powder is used as a starting material, to provide a highly oriented, e.g., approximately 90% of the crystal particles have a common orientation, superconducting matrix capable of supporting large current densities.

  3. Preferential orientation of metal oxide superconducting materials by mechanical means

    DOE Patents [OSTI]

    Capone, D.W.

    1990-11-27

    A superconductor comprised of a polycrystalline metal oxide such as YBa[sub 2]Cu[sub 3]O[sub 7[minus]X] (where 0 < X < 0.5) is capable of accommodating very large current densities. By aligning the two-dimensional Cu-O layers which carry the current in the superconducting state in the a- and b-directions, i.e., within the basal plane, a high degree of crystalline axes alignment is provided between adjacent grains permitting the metal oxide material to accommodate high current densities. The orthorhombic crystalline particles have a tendency to lie down on one of the longer sides, i.e., on the a- or b-direction. Aligning the crystals in this orientation is accomplished by mechanical working of the material such as by extrusion, tape casting or slip casting, provided a single crystal powder is used as a starting material, to provide a highly oriented, e.g., approximately 90% of the crystal particles have a common orientation, superconducting matrix capable of supporting large current densities. 3 figs.

  4. Bipolar plating of metal contacts onto oxide interconnection for solid oxide electrochemical cell

    DOE Patents [OSTI]

    Isenberg, A.O.

    1987-03-10

    Disclosed is a method of forming an adherent metal deposit on a conducting layer of a tube sealed at one end. The tube is immersed with the sealed end down into an aqueous solution containing ions of the metal to be deposited. An ionically conducting aqueous fluid is placed inside the tube and a direct current is passed from a cathode inside the tube to an anode outside the tube. Also disclosed is a multi-layered solid oxide fuel cell tube which consists of an inner porous ceramic support tube, a porous air electrode covering the support tube, a non-porous electrolyte covering a portion of the air electrode, a non-porous conducting interconnection covering the remaining portion of the electrode, and a metal deposit on the interconnection. 1 fig.

  5. Bipolar plating of metal contacts onto oxide interconnection for solid oxide electrochemical cell

    DOE Patents [OSTI]

    Isenberg, Arnold O. (Forest Hills Boro, PA)

    1987-01-01

    Disclosed is a method of forming an adherent metal deposit on a conducting layer of a tube sealed at one end. The tube is immersed with the sealed end down into an aqueous solution containing ions of the metal to be deposited. An ionically conducting aqueous fluid is placed inside the tube and a direct current is passed from a cathode inside the tube to an anode outside the tube. Also disclosed is a multi-layered solid oxide fuel cell tube which consists of an inner porous ceramic support tube, a porous air electrode covering the support tube, a non-porous electrolyte covering a portion of the air electrode, a non-porous conducting interconnection covering the remaining portion of the electrode, and a metal deposit on the interconnection.

  6. Visible-light-induced instability in amorphous metal-oxide based TFTs for transparent electronics

    SciTech Connect (OSTI)

    Ha, Tae-Jun

    2014-10-15

    We investigate the origin of visible-light-induced instability in amorphous metal-oxide based thin film transistors (oxide-TFTs) for transparent electronics by exploring the shift in threshold voltage (V{sub th}). A large hysteresis window in amorphous indium-gallium-zinc-oxide (a-IGZO) TFTs possessing large optical band-gap (?3 eV) was observed in a visible-light illuminated condition whereas no hysteresis window was shown in a dark measuring condition. We also report the instability caused by photo irradiation and prolonged gate bias stress in oxide-TFTs. Larger V{sub th} shift was observed after photo-induced stress combined with a negative gate bias than the sum of that after only illumination stress and only negative gate bias stress. Such results can be explained by trapped charges at the interface of semiconductor/dielectric and/or in the gate dielectric which play a role in a screen effect on the electric field applied by gate voltage, for which we propose that the localized-states-assisted transitions by visible-light absorption can be responsible.

  7. Beyond the Lone-Pair Model for Structurally Distorted Metal Oxides

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Beyond the Lone-Pair Model for Structurally Distorted Metal Oxides Beyond the Lone-Pair Model for Structurally Distorted Metal Oxides Print Wednesday, 28 February 2007 00:00 "Ferroelectricity," by analogy to ferromagnetism, is defined as the presence of spontaneous electrical polarization in a material, often arising from distortions in the material's crystal structure. In oxides of the metals lead and bismuth, such distortions were for many years attributed to the existence of

  8. Method of adhesion between an oxide layer and a metal layer

    DOE Patents [OSTI]

    Jennison, Dwight R.; Bogicevic, Alexander; Kelber, Jeffry A.; Chambers, Scott A.

    2004-09-14

    A method of controlling the wetting characteristics and increasing the adhesion between a metal and an oxide layer. By introducing a negatively-charged species to the surface of an oxide layer, layer-by-layer growth of metal deposited onto the oxide surface is promoted, increasing the adhesion strength of the metal-oxide interface. The negatively-charged species can either be deposited onto the oxide surface or a compound can be deposited that dissociates on, or reacts with, the surface to form the negatively-charged species. The deposited metal adatoms can thereby bond laterally to the negatively-charged species as well as vertically to the oxide surface as well as react with the negatively charged species, be oxidized, and incorporated on or into the surface of the oxide.

  9. NANOSTRUCTURED METAL OXIDE CATALYSTS VIA BUILDING BLOCK SYNTHESES

    SciTech Connect (OSTI)

    Craig E. Barnes

    2013-03-05

    A broadly applicable methodology has been developed to prepare new single site catalysts on silica supports. This methodology requires of three critical components: a rigid building block that will be the main structural and compositional component of the support matrix; a family of linking reagents that will be used to insert active metals into the matrix as well as cross link building blocks into a three dimensional matrix; and a clean coupling reaction that will connect building blocks and linking agents together in a controlled fashion. The final piece of conceptual strategy at the center of this methodology involves dosing the building block with known amounts of linking agents so that the targeted connectivity of a linking center to surrounding building blocks is obtained. Achieving targeted connectivities around catalytically active metals in these building block matrices is a critical element of the strategy by which single site catalysts are obtained. This methodology has been demonstrated with a model system involving only silicon and then with two metal-containing systems (titanium and vanadium). The effect that connectivity has on the reactivity of atomically dispersed titanium sites in silica building block matrices has been investigated in the selective oxidation of phenols to benezoquinones. 2-connected titanium sites are found to be five times as active (i.e. initial turnover frequencies) than 4-connected titanium sites (i.e. framework titanium sites).

  10. Ab-initio study of transition metal hydrides

    SciTech Connect (OSTI)

    Sharma, Ramesh; Shukla, Seema Dwivedi, Shalini Sharma, Yamini

    2014-04-24

    We have performed ab initio self consistent calculations based on Full potential linearized augmented plane wave (FP-LAPW) method to investigate the optical and thermal properties of yttrium hydrides. From the band structure and density of states, the optical absorption spectra and specific heats have been calculated. The band structure of Yttrium metal changes dramatically due to hybridization of Y sp orbitals with H s orbitals and there is a net charge transfer from metal to hydrogen site. The electrical resistivity and specific heats of yttrium hydrides are lowered but the thermal conductivity is slightly enhanced due to increase in scattering from hydrogen sites.

  11. Modeling and experimental studies of oxide covered metal surfaces: TiO{sub 2}/Ti a model system. Progress report

    SciTech Connect (OSTI)

    Smyrl, W.H.

    1991-12-31

    Prior work in our laboratories at the Corrosion Research Center has shown that thin, anodic TiO{sub 2} films formed by the Slow Growth Mode (SGM) on polycrystalline titanium and microcrystalline with a texture that varies from one metal grain to another. Furthermore, the underlying metal grains are mapped by the photoelectrochemical response of the oxide. The same characteristics have also been demonstrated in our laboratory for ZnO grown on Zn. The TiO{sub 2}/Ti system has been chosen for study both because of its importance in energy systems, and because it can serve as a model system for other metal-metal oxide couples. The investigations of anodic TiO{sub 2} films on Ti have shown that the properties of thin films are consistent with the rutile form of the oxide. Both experimental data and theoretical calculations show the close resemblance to results on single crystal TiO{sub 2}. Furthermore, the modeling studies reveal that the optical transitions near the bandedge arise from the bulk band structure. The photoelectrochemical properties of anodic TiO{sub 2} films have now been shown to obey the simple Gaertner-Butler model for the semiconductor-electrolyte interface, with a few modifications. The most important deviation has now been shown to be a result of multiple internal reflections in the oxide film.

  12. Modeling and experimental studies of oxide covered metal surfaces: TiO sub 2 /Ti a model system

    SciTech Connect (OSTI)

    Smyrl, W.H.

    1991-01-01

    Prior work in our laboratories at the Corrosion Research Center has shown that thin, anodic TiO{sub 2} films formed by the Slow Growth Mode (SGM) on polycrystalline titanium and microcrystalline with a texture that varies from one metal grain to another. Furthermore, the underlying metal grains are mapped by the photoelectrochemical response of the oxide. The same characteristics have also been demonstrated in our laboratory for ZnO grown on Zn. The TiO{sub 2}/Ti system has been chosen for study both because of its importance in energy systems, and because it can serve as a model system for other metal-metal oxide couples. The investigations of anodic TiO{sub 2} films on Ti have shown that the properties of thin films are consistent with the rutile form of the oxide. Both experimental data and theoretical calculations show the close resemblance to results on single crystal TiO{sub 2}. Furthermore, the modeling studies reveal that the optical transitions near the bandedge arise from the bulk band structure. The photoelectrochemical properties of anodic TiO{sub 2} films have now been shown to obey the simple Gaertner-Butler model for the semiconductor-electrolyte interface, with a few modifications. The most important deviation has now been shown to be a result of multiple internal reflections in the oxide film.

  13. Toward Photochemical Water Splitting Using Band-Gap-Narrowed Semiconductors and Transition-Metal Based Molecular Catalysts

    SciTech Connect (OSTI)

    Muckerman,J.T.; Rodriguez, J.A.; Fujita, E.

    2009-06-07

    We are carrying out coordinated theoretical and experimental studies of toward photochemical water splitting using band-gap-narrowed semiconductors (BGNSCs) with attached multi-electron molecular water oxidation and hydrogen production catalysts. We focus on the coupling between the materials properties and the H{sub 2}O redox chemistry, with an emphasis on attaining a fundamental understanding of the individual elementary steps in the following four processes: (1) Light-harvesting and charge-separation of stable oxide or oxide-derived semiconductors for solar-driven water splitting, including the discovery and characterization of the behavior of such materials at the aqueous interface; (2) The catalysis of the four-electron water oxidation by dinuclear hydroxo transition-metal complexes with quinonoid ligands, and the rational search for improved catalysts; (3) Transfer of the design principles learned from the elucidation of the DuBois-type hydrogenase model catalysts in acetonitrile to the rational design of two-electron hydrogen production catalysts for aqueous solution; (4) Combining these three elements to examine the function of oxidation catalysts on BGNSC photoanode surfaces and hydrogen production catalysts on cathode surfaces at the aqueous interface to understand the challenges to the efficient coupling of the materials functions.

  14. Transition metals on the (0001) surface of graphite: Fundamental aspects of adsorption, diffusion, and morphology

    SciTech Connect (OSTI)

    Appy, David [Ames Laboratory; Lei, Huaping [Ames Laboratory; Wang, Cai-Zhuang [Ames Laboratory; Tringides, Michael C [Ames Laboratory; Liu, Da-Jiang [Ames Laboratory; Evans, James W [Ames Laboratory; Thiel, Patricia A [Ames Laboratory

    2014-08-01

    In this article, we review basic information about the interaction of transition metal atoms with the (0 0 0 1) surface of graphite, especially fundamental phenomena related to growth. Those phenomena involve adatom-surface bonding, diffusion, morphology of metal clusters, interactions with steps and sputter-induced defects, condensation, and desorption. General traits emerge which have not been summarized previously. Some of these features are rather surprising when compared with metal-on-metal adsorption and growth. Opportunities for future work are pointed out.

  15. Cyclopentadienyl-containing low-valent early transition metal olefin polymerization catalysts

    DOE Patents [OSTI]

    Marks, Tobin J.; Luo, Lubin; Yoon, Sung Cheol

    2007-01-09

    A catalyst system useful to polymerize and co-polymerize polar and non-polar olefin monomers is formed by in situ reduction with a reducing agent of a catalyst precursor comprising {Cp*MRR'.sub.n}.sup.+{A}.sup.- wherein Cp* is a cyclopentadienyl or substituted cyclopentadienyl moiety; M is an early transition metal; R is a C.sub.1 C.sub.20 hydrocarbyl; R' are independently selected from hydride, C.sub.1 C.sub.20 hydrocarbyl, SiR''.sub.3, NR''.sub.2, OR'', SR'', GeR''.sub.3, SnR''.sub.3, and C.dbd.C-containing groups (R''=C.sub.1 C.sub.10 hydrocarbyl); n is an integer selected to balance the oxidation state of M; and A is a suitable non-coordinating anionic cocatalyst or precursor. This catalyst system may form stereoregular olefin polymers including syndiotactic polymers of styrene and methylmethacrylate and isotactic copolymers of polar and nonpolar olefin monomers such as methylmethacrylate and styrene.

  16. Cyclopentadienyl-containing low-valent early transition metal olefin polymerization catalysts

    DOE Patents [OSTI]

    Marks, Tobin J.; Luo, Lubin; Yoon, Sung Cheol

    2003-12-30

    A catalyst system useful to polymerize and co-polymerize polar and non-polar olefin monomers is formed by in situ reduction with a reducing agent of a catalyst precursor comprising wherein Cp* is a cyclopentadienyl or substituted cyclopentadienyl moiety; M is an early transition metal; R is a C.sub.1 -C.sub.20 hydrocarbyl; R' are independently selected from hydride, C.sub.1 -C.sub.20 hydrocarbyl, SiR".sub.3, NR".sub.2, OR", SR", GeR".sub.3, SnR".sub.3, and C.dbd.C containing groups (R".dbd.C.sub.1 -C.sub.10 hydrocarbyl); n is an integer selected to balance the oxidation state of M; and A is a suitable non-coordinating anionic cocatalyst or precursor. This catalyst system may form stereoregular olefin polymers including syndiotactic polymers of styrene and methylmethacrylate and isotactic copolymers of polar and nonpolar olefin monomers such as methylmethacrylate and styrene.

  17. Cyclopentadienyl-containing low-valent early transition metal olefin polymerization catalysts

    DOE Patents [OSTI]

    Marks, Tobin J.; Luo, Lubin; Yoon, Sung Cheol

    2006-10-10

    A catalyst system useful to polymerize and co-polymerize polar and non-polar olefin monomers is formed by in situ reduction with a reducing agent of a catalyst precursor comprising {Cp*MRR'.sub.n}.sup.+{A}.sup.- wherein Cp* is a cyclopentadienyl or substituted cyclopentadienyl moiety; M is an early transition metal; R is a C.sub.1 C.sub.20 hydrocarbyl; R' are independently selected from hydride, C.sub.1 C.sub.20 hydrocarbyl, SiR''.sub.3, NR''.sub.2, OR'', SR'', GeR''.sub.3, SnR''.sub.3, and C.dbd.C-containing groups (R''=C.sub.1 C.sub.10 hydrocarbyl); n is an integer selected to balance the oxidation state of M; and A is a suitable non-coordinating anionic cocatalyst or precursor. This catalyst system may form stereoregular olefin polymers including syndiotactic polymers of styrene and methylmethacrylate and isotactic copolymers of polar and nonpolar olefin monomers such as methylmethacrylate and styrene.

  18. Cyclopentadienyl-containing low-valent early transition metal olefin polymerization catalysts

    DOE Patents [OSTI]

    Marks, Tobin J.; Luo, Lubin; Yoon, Sung Cheol

    2003-04-08

    A catalyst system useful to polymerize and co-polymerize polar and non-polar olefin monomers is formed by in situ reduction with a reducing agent of a catalyst precursor comprising {Cp*MRR'.sub.n }.sup.+ {A}.sup.- wherein Cp* is a cyclopentadienyl or substituted cyclopentadienyl moiety; M is an early transition metal; R is a C.sub.1 -C.sub.20 hydrocarbyl; R' are independently selected from hydride, C.sub.1 -C.sub.20 hydrocarbyl, SiR".sub.3, NR".sub.2, OR", SR", GeR".sub.3, and SnR".sub.3 containing groups (R"=C.sub.1 -C.sub.10 hydrocarbyl); n is an integer selected to balance the oxidation state of M; and A is a suitable non-coordinating anionic cocatalyst or precursor. This catalyst system may form stereoregular olefin polymers including syndiotactic polymers of styrene and methylmethacrylate and isotactic copolymers of polar and nonpolar olefin monomers such as methylmethacrylate and styrene.

  19. Cyclopentadienyl-Containing Low-Valent Early Transition Metal Olefin Polymerization Catalysts

    DOE Patents [OSTI]

    Marks, Tobin J.; Luo, Lubin; Yoon, Sung Cheol

    2004-06-08

    A catalyst system useful to polymerize and co-polymerize polar and non-polar olefin monomers is formed by in situ reduction with a reducing agent of a catalyst precursor comprising {Cp*MRR'.sub.n }.sup.+ {A}.sup.- wherein Cp* is a cyclopentadienyl or substituted cyclopentadienyl moiety; M is an early transition metal; R is a C.sub.1 -C.sub.20 hydrocarbyl; R' are independently selected from hydride, C.sub.1 -C.sub.20 hydrocarbyl, SiR".sub.3, NR".sub.2, OR", SR", GeR".sub.3, SnR".sub.3, and C.dbd.C-containing groups (R"=C.sub.1 -C.sub.10 hydrocarbyl); n is an integer selected to balance the oxidation state of M; and A is a suitable non-coordinating anionic cocatalyst or precursor. This catalyst system may form stereoregular olefin polymers including syndiotactic polymers of styrene and methylmethacrylate and isotactic copolymers of polar and nonpolar olefin monomers such as methylmethacrylate and styrene.

  20. CO oxidation on gold-supported iron oxides: New insights into strong oxide–metal interactions

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Yu, Liang; Liu, Yun; Yang, Fan; Evans, Jaime; Rodriguez, José A.; Liu, Ping

    2015-07-14

    Very active FeOx–Au catalysts for CO oxidation are obtained after depositing nanoparticles of FeO, Fe3O4, and Fe2O3 on a Au(111) substrate. Neither FeO nor Fe2O3 is stable under the reaction conditions. Under an environment of CO/O2, they undergo oxidation (FeO) or reduction (Fe2O3) to yield nanoparticles of Fe3O4 that are not formed in a bulk phase. Using a combined experimental and theoretical approach, we show a strong oxide–metal interaction (SOMI) between Fe3O4 nanostructures and Au(111), which gives the oxide special properties, allows the formation of an active phase, and provides a unique interface to facilitate a catalytic reaction. This workmore » highlights the important role that the SOMI can play in enhancing the catalytic performance of the oxide component in metal–oxide catalysts.« less

  1. Sodiation kinetics of metal oxide conversion electrodes: A comparative study with lithiation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    He, Kai; Lin, Feng; Zhu, Yizhou; Yu, Xiqian; Li, Jing; Lin, Ruoqian; Nordlund, Dennis; Weng, Tsu Chien; Richards, Ryan M.; Yang, Xiao -Qing; et al

    2015-08-19

    The development of sodium ion batteries (NIBs) can provide an alternative to lithium ion batteries (LIBs) for sustainable, low-cost energy storage. However, due to the larger size and higher m/e ratio of the sodium ion compared to lithium, sodiation reactions of candidate electrodes are expected to differ in significant ways from the corresponding lithium ones. In this work, we investigated the sodiation mechanism of a typical transition metal-oxide, NiO, through a set of correlated techniques, including electrochemical and synchrotron studies, real-time electron microscopy observation, and ab initio molecular dynamics (MD) simulations. We found that a crystalline Na₂O reaction layer thatmore » was formed at the beginning of sodiation plays an important role in blocking the further transport of sodium ions. In addition, sodiation in NiO exhibits a “shrinking-core” mode that results from a layer-by-layer reaction, as identified by ab initio MD simulations. For lithiation, however, the formation of Li anti-site defects significantly distorts the local NiO lattice that facilitates Li insertion, thus enhancing the overall reaction rate. These observations delineate the mechanistic difference between sodiation and lithiation in metal-oxide conversion materials. More importantly, our findings identify the importance of understanding the role of reaction layers on the functioning of electrodes and thus provide critical insights into further optimizing NIB materials through surface engineering.« less

  2. Sodiation kinetics of metal oxide conversion electrodes: A comparative study with lithiation

    SciTech Connect (OSTI)

    He, Kai; Lin, Feng; Zhu, Yizhou; Yu, Xiqian; Li, Jing; Lin, Ruoqian; Nordlund, Dennis; Weng, Tsu Chien; Richards, Ryan M.; Yang, Xiao -Qing; Doeff, Marca M.; Stach, Eric A.; Mo, Yifei; Xin, Huolin L.; Su, Dong

    2015-08-19

    The development of sodium ion batteries (NIBs) can provide an alternative to lithium ion batteries (LIBs) for sustainable, low-cost energy storage. However, due to the larger size and higher m/e ratio of the sodium ion compared to lithium, sodiation reactions of candidate electrodes are expected to differ in significant ways from the corresponding lithium ones. In this work, we investigated the sodiation mechanism of a typical transition metal-oxide, NiO, through a set of correlated techniques, including electrochemical and synchrotron studies, real-time electron microscopy observation, and ab initio molecular dynamics (MD) simulations. We found that a crystalline Na?O reaction layer that was formed at the beginning of sodiation plays an important role in blocking the further transport of sodium ions. In addition, sodiation in NiO exhibits a shrinking-core mode that results from a layer-by-layer reaction, as identified by ab initio MD simulations. For lithiation, however, the formation of Li anti-site defects significantly distorts the local NiO lattice that facilitates Li insertion, thus enhancing the overall reaction rate. These observations delineate the mechanistic difference between sodiation and lithiation in metal-oxide conversion materials. More importantly, our findings identify the importance of understanding the role of reaction layers on the functioning of electrodes and thus provide critical insights into further optimizing NIB materials through surface engineering.

  3. Aqueous medium induced optical transitions in cerium oxide nanoparticles

    SciTech Connect (OSTI)

    Inerbaev, Talgat M.; Karakoti, Ajay S.; Kuchibhatla, S. V. N. T.; Kumar, Amit; Masunov, Artem E.; Seal, Sudipta

    2015-03-07

    Experimental and theoretical investigations were performed to investigate the effect of water on optical properties of nanoceria as a function of Ce3+ concentration. Theoretical studies based on density functional plane-wave calculations reveal that the indirect optical transitions in bare ceria nanoparticles are red-shifted with an increase in the concentration of Ce3+. However, ceria nanoparticles model with adsorbed water molecules show a blue shift in the indirect optical spectra under identical conditions. Direct optical transitions are almost independent of Ce3+ concentration but show a pronounced blue shift in the aqueous environment relative to the bare nanoparticles. The theoretical study is consistent with our experimental observation in difference of shift behaviour in bare and aqueous suspended ceria nanoparticles. This change from red- to blue-shift in indirect optical transitions is associated with the polarization effect of water molecules on f-electron states.

  4. Fabrication of carbon nanotube films from alkyne-transition metal complexes

    DOE Patents [OSTI]

    Iyer, Vivekanantan S. (Delft, NL); Vollhardt, K. Peter C. (Oakland, CA)

    2007-08-28

    A simple method for the production or synthesis of carbon nanotubes as free-standing films or nanotube mats by the thermal decomposition of transition metal complexed alkynes with aryl, alkyl, alkenyl, or alkynyl substituents. In particular, transition metal (e.g. Co, Ni, Fe, Mo) complexes of diarylacetylenes, e.g. diphenylacetylene, and solid mixtures of these complexes with suitable, additional carbon sources are heated in a vessel. More specifically, the heating of the transition metal complex is completed at a temperature between 400-800.degree. C. and more particularly 550-700.degree. C. for between 0.1 to 24 hours and more particularly 0.5-3 hours in a sealed vessel under a partial pressure of argon or helium.

  5. Oxidation catalysts comprising metal exchanged hexaaluminate wherein the metal is Sr, Pd, La, and/or Mn

    DOE Patents [OSTI]

    Wickham, David (Boulder, CO); Cook, Ronald (Lakewood, CO)

    2008-10-28

    The present invention provides metal-exchanged hexaaluminate catalysts that exhibit good catalytic activity and/or stability at high temperatures for extended periods with retention of activity as combustion catalysts, and more generally as oxidation catalysts, that make them eminently suitable for use in methane combustion, particularly for use in natural gas fired gas turbines. The hexaaluminate catalysts of this invention are of particular interest for methane combustion processes for minimization of the generation of undesired levels (less than about 10 ppm) of NOx species. Metal exchanged hexaaluminate oxidation catalysts are also useful for oxidation of volatile organic compounds (VOC), particularly hydrocarbons. Metal exchanged hexaaluminate oxidation catalysts are further useful for partial oxidation, particularly at high temperatures, of reduced species, particularly hydrocarbons (alkanes and alkenes).

  6. The carburization of transition metal molybdates (MxMoO₄, M= Cu, Ni or Co) and the generation of highly active metal/carbide catalysts for CO₂ hydrogenation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Rodriguez, Jose A.; Xu, Wenqian; Ramirez, Pedro J.; Stachiola, Dario; Brito, Joaquin L.

    2015-05-06

    A new approach has been tested for the preparation of metal/Mo₂C catalysts using mixed-metal oxide molybdates as precursors. Synchrotron-based in situ time-resolved X-ray diffraction was used to study the reduction and carburization processes of Cu₃(MoO₄)₂(OH)₂, a-NiMoO₄ and CoMoO₄•nH₂O by thermal treatment under mixtures of hydrogen and methane. In all cases, the final product was β-Mo₂C and a metal phase (Cu, Ni, or Co), but the transition sequence varied with the different metals, and it could be related to the reduction potential of the Cu²⁺, Ni²⁺ and Co²⁺ cations inside each molybdate. The synthesized Cu/Mo₂C, Ni/Mo₂C and Co/Mo₂C catalysts were highlymore » active for the hydrogenation of CO₂. The metal/Mo₂C systems exhibited large variations in the selectivity towards methanol, methane and CnH₂n₊₂ (n > 2) hydrocarbons depending on the nature of the supported metal and its ability to cleave C-O bonds. Cu/Mo₂C displayed a high selectivity for CO and methanol production. Ni/Mo₂C and Co/Mo₂C were the most active catalysts for the activation and full decomposition of CO₂, showing high selectivity for the production of methane (Ni case) and CnH₂n₊₂ (n > 2) hydrocarbons (Co case).« less

  7. Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2 Print The grand goal motivating femtosecond studies of condensed-matter dynamics is to directly measure the structural pathways that connect different crystallographic, electronic, and magnetic phases of solids, as well as the short-lived transition states between reactants and products in chemical and biochemical reactions. Researchers from Berkeley Lab and the Université du Québec have taken a big step forward by adding

  8. Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2 Print The grand goal motivating femtosecond studies of condensed-matter dynamics is to directly measure the structural pathways that connect different crystallographic, electronic, and magnetic phases of solids, as well as the short-lived transition states between reactants and products in chemical and biochemical reactions. Researchers from Berkeley Lab and the Université du Québec have taken a big step forward by adding

  9. Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2 Print The grand goal motivating femtosecond studies of condensed-matter dynamics is to directly measure the structural pathways that connect different crystallographic, electronic, and magnetic phases of solids, as well as the short-lived transition states between reactants and products in chemical and biochemical reactions. Researchers from Berkeley Lab and the Université du Québec have taken a big step forward by adding

  10. Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2 Print The grand goal motivating femtosecond studies of condensed-matter dynamics is to directly measure the structural pathways that connect different crystallographic, electronic, and magnetic phases of solids, as well as the short-lived transition states between reactants and products in chemical and biochemical reactions. Researchers from Berkeley Lab and the Université du Québec have taken a big step forward by adding

  11. Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2 Print The grand goal motivating femtosecond studies of condensed-matter dynamics is to directly measure the structural pathways that connect different crystallographic, electronic, and magnetic phases of solids, as well as the short-lived transition states between reactants and products in chemical and biochemical reactions. Researchers from Berkeley Lab and the Université du Québec have taken a big step forward by adding

  12. Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Femtosecond NEXAFS of Photoinduced Insulator-Metal Transition in VO2 Print The grand goal motivating femtosecond studies of condensed-matter dynamics is to directly measure the structural pathways that connect different crystallographic, electronic, and magnetic phases of solids, as well as the short-lived transition states between reactants and products in chemical and biochemical reactions. Researchers from Berkeley Lab and the Université du Québec have taken a big step forward by adding

  13. Phase transition and metallization of FeO at high pressures and

    Office of Scientific and Technical Information (OSTI)

    temperatures (Journal Article) | SciTech Connect Journal Article: Phase transition and metallization of FeO at high pressures and temperatures Citation Details In-Document Search Title: Phase transition and metallization of FeO at high pressures and temperatures Wuestite, Fe{sub 1-x}O, is an important component in the mineralogy of Earth's lower mantle and may also be a component of the core. Therefore its high pressure-temperature behavior, including its electronic structure, is essential

  14. CO2 Induced Phase Transitions in Diamine-Appended Metal-Organic Frameworks

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    | Center for Gas SeparationsRelevant to Clean Energy Technologies | Blandine Jerome CO2 Induced Phase Transitions in Diamine-Appended Metal-Organic Frameworks Previous Next List Vlaisavljevich, Bess; Odoh, Samuel O.; Schnell, Sondre K.; Dzubak, Allison; Lee, Kyuho; Planas, Nora; Neaton, Jeffrey B.; Gagliardi, Laura; and Smit, Berend. CO2 Induced Phase Transitions in Diamine-Appended Metal-Organic Frameworks. Chem. Sci., 6, 5177-5185 (2015). DOI: 10.1039/c5sc01828e CO2 induced phase

  15. Insulator-to-Metal Transition of Vanadium Dioxide | U.S. DOE Office of

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science (SC) Insulator-to-Metal Transition of Vanadium Dioxide Basic Energy Sciences (BES) BES Home About Research Facilities Science Highlights Benefits of BES Funding Opportunities Basic Energy Sciences Advisory Committee (BESAC) Community Resources Contact Information Basic Energy Sciences U.S. Department of Energy SC-22/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3081 F: (301) 903-6594 E: Email Us More Information » 03.01.15 Insulator-to-Metal

  16. Method of dissolving metal oxides with di- or polyphosphonic acid and a redundant

    DOE Patents [OSTI]

    Horwitz, Earl P. (Argonne, IL); Chiarizia, Renato (Argonne, IL)

    1996-01-01

    A method of dissolving metal oxides using a mixture of a di- or polyphosphonic acid and a reductant wherein each is present in a sufficient amount to provide a synergistic effect with respect to the dissolution of metal oxides and optionally containing corrosion inhibitors and pH adjusting agents.

  17. Self assembled multi-layer nanocomposite of graphene and metal oxide materials

    DOE Patents [OSTI]

    Liu, Jun; Choi, Daiwon; Kou, Rong; Nie, Zimin; Wang, Donghai; Yang, Zhenguo

    2014-09-16

    Nanocomposite materials having at least two layers, each layer consisting of one metal oxide bonded to at least one graphene layer were developed. The nanocomposite materials will typically have many alternating layers of metal oxides and graphene layers, bonded in a sandwich type construction and will be incorporated into an electrochemical or energy storage device.

  18. Self assembled multi-layer nanocomposite of graphene and metal oxide materials

    DOE Patents [OSTI]

    Liu, Jun; Aksay, Ilhan A; Choi, Daiwon; Kou, Rong; Nie, Zimin; Wang, Donghai; Yang, Zhenguo

    2015-04-28

    Nanocomposite materials having at least two layers, each layer consisting of one metal oxide bonded to at least one graphene layer were developed. The nanocomposite materials will typically have many alternating layers of metal oxides and graphene layers, bonded in a sandwich type construction and will be incorporated into an electrochemical or energy storage device.

  19. Self assembled multi-layer nanocomposite of graphene and metal oxide materials

    DOE Patents [OSTI]

    Liu, Jun; Aksay, Ilhan A; Choi, Daiwon; Kou, Rong; Nie, Zimin; Wang, Donghai; Yang, Zhenguo

    2013-10-22

    Nanocomposite materials having at least two layers, each layer consisting of one metal oxide bonded to at least one graphene layer were developed. The nanocomposite materials will typically have many alternating layers of metal oxides and graphene layers, bonded in a sandwich type construction and will be incorporated into an electrochemical or energy storage device.

  20. Recycling of rare earth metals from rare earth-transition metal alloy scrap by liquid metal extraction

    DOE Patents [OSTI]

    Ellis, Timothy W. (Ames, IA); Schmidt, Frederick A. (Ames, IA)

    1995-08-01

    Method of treating rare earth metal-bearing scrap, waste or other material (e.g. Nd--Fe--B or Dy--Tb--Fe scrap) to recover the rare earth metal comprising melting the rare earth metal-bearing material, melting a Group IIA metal extractant, such as Mg, Ca, or Ba, in which the rare earth is soluble in the molten state, and contacting the melted material and melted extractant at a temperature and for a time effective to extract the rare earth from the melted material into the melted extractant. The rare earth metal is separated from the extractant metal by vacuum sublimation or distillation.

  1. Recycling of rare earth metals from rare earth-transition metal alloy scrap by liquid metal extraction

    DOE Patents [OSTI]

    Ellis, T.W.; Schmidt, F.A.

    1995-08-01

    A method is described for treating rare earth metal-bearing scrap, waste or other material (e.g. Nd--Fe--B or Dy--Tb--Fe scrap) to recover the rare earth metal comprising melting the rare earth metal-bearing material, melting a Group IIA metal extractant, such as Mg, Ca, or Ba, in which the rare earth is soluble in the molten state, and contacting the melted material and melted extractant at a temperature and for a time effective to extract the rare earth from the melted material into the melted extractant. The rare earth metal is separated from the extractant metal by vacuum sublimation or distillation. 2 figs.

  2. Sharp semiconductor-to-metal transition of VO{sub 2} thin films on glass substrates

    SciTech Connect (OSTI)

    Jian, Jie; Chen, Aiping [Department of Electrical and Computer Engineering, Texas A and M University, College Station, Texas 77843-3128 (United States); Zhang, Wenrui [Material Science and Engineering Program, Texas A and M University, College Station, Texas 77843-3128 (United States); Wang, Haiyan, E-mail: wangh@ece.tamu.edu [Department of Electrical and Computer Engineering, Texas A and M University, College Station, Texas 77843-3128 (United States); Material Science and Engineering Program, Texas A and M University, College Station, Texas 77843-3128 (United States)

    2013-12-28

    Outstanding phase transition properties of vanadium dioxide (VO{sub 2}) thin films on amorphous glass were achieved and compared with the ones grown on c-cut sapphire and Si (111) substrates, all by pulsed laser deposition. The films on glass substrate exhibit a sharp semiconductor-to-metal transition (?4.3?C) at a near bulk transition temperature of ?68.4?C with an electrical resistance change as high as 3.2??10{sup 3} times. The excellent phase transition properties of the films on glass substrate are correlated with the large grain size and low defects density achieved. The phase transition properties of VO{sub 2} films on c-cut sapphire and Si (111) substrates were found to be limited by the high defect density.

  3. Highly Emissive Transition Metal Ion Doped Semiconducting Nanocrystals

    SciTech Connect (OSTI)

    Jana, Santanu; Srivastava, Bhupendra B.; Pradhan, Narayan; Sarma, D. D.

    2011-07-15

    Doped semiconductor nanocrystals (d-dots), specifically ones not containing heavy metal ions, have the potential to become a class of mainstream emissive materials. Mn- and Cu-doped ZnSe or ZnS d-dots can cover an emission window similar to that of the current workhorse of intrinsic quantum dot (q-dots) emitters, CdSe nanocrystals. We synthesized high quality stable Cu doped ZnSe in nonpolar as well as polar solvent. The emission intensity of these doped nanocrystals is found stable for months under UV irradiation, after different multifunctional ligand which is important for any biological detection. We have also synthesized the stable Mn doped ZnS in nonpolar solvent more than 50% QY.. The doped nanocrystals are characterized by TEM, XRD, EPR and ICP analysis.

  4. Process and apparatus for generating elemental sulfur and re-usable metal oxide from spent metal sulfide sorbents

    DOE Patents [OSTI]

    Ayala, Raul E. (Clifton Park, NY); Gal, Eli (Lititz, PA)

    1995-01-01

    A process and apparatus for generating elemental sulfur and re-usable metal oxide from spent metal-sulfur compound. Spent metal-sulfur compound is regenerated to re-usable metal oxide by moving a bed of spent metal-sulfur compound progressively through a single regeneration vessel having a first and second regeneration stage and a third cooling and purging stage. The regeneration is carried out and elemental sulfur is generated in the first stage by introducing a first gas of sulfur dioxide which contains oxygen at a concentration less than the stoichiometric amount required for complete oxidation of the spent metal-sulfur compound. A second gas containing sulfur dioxide and excess oxygen at a concentration sufficient for complete oxidation of the partially spent metal-sulfur compound, is introduced into the second regeneration stage. Gaseous sulfur formed in the first regeneration stage is removed prior to introducing the second gas into the second regeneration stage. An oxygen-containing gas is introduced into the third cooling and purging stage. Except for the gaseous sulfur removed from the first stage, the combined gases derived from the regeneration stages which are generally rich in sulfur dioxide and lean in oxygen, are removed from the regenerator as an off-gas and recycled as the first and second gas into the regenerator. Oxygen concentration is controlled by adding air, oxygen-enriched air or pure oxygen to the recycled off-gas.

  5. Microbial-mediated method for metal oxide nanoparticle formation...

    Office of Scientific and Technical Information (OSTI)

    wherein said combination of reaction components comprise: metal-reducing microbes, a culture medium suitable for sustaining said metal-reducing microbes, an effective...

  6. Electrocaloric effect of metal-insulator transition in VO{sub 2}

    SciTech Connect (OSTI)

    Matsunami, Daichi; Fujita, Asaya

    2015-01-26

    The electrocaloric effect was observed in association with an electric-field induced metal-insulator transition in VO{sub 2} using a calorimetric measurement under an applied voltage. For a VO{sub 2} plate with a 0.4 mm thickness located in the center of a capacitor-like structure, the metal-insulator transition was manipulated by applying a few volts. The occurrence of a transition in such a thick sample with relatively low voltage indicates that a surface charge accumulation mechanism is effective. The isothermal entropy change reached 94 J kg{sup −1} K{sup −1}, while the adiabatic temperature change was calculated as −3.8 K under a voltage change of 0–3 V. The large entropy change is attributed to correlation of the complex freedom among spin, charge, and lattice.

  7. Magnetoelectric effects and valley-controlled spin quantum gates in transition metal dichalcogenide bilayers

    SciTech Connect (OSTI)

    Gong, Zhirui; Liu, G. B.; Yu, Hongyi; Xiao, Di; Cui, Xiaodong; Xu, Xiaodong; Yao, Wang

    2013-01-01

    In monolayer group-VI transition metal dichalcogenides, charge carriers have spin and valley degrees of freedom, both associated with magnetic moments. On the other hand, the layer degree of freedom in multilayers is associated with electrical polarization. Here we show that transition metal dichalcogenide bilayers offer an unprecedented platform to realize a strong coupling between the spin, valley and layer pseudospin of holes. Such coupling gives rise to the spin Hall effect and spin-dependent selection rule for optical transitions in inversion symmetric bilayer and leads to a variety of magnetoelectric effects permitting quantum manipulation of these electronic degrees of freedom. Oscillating electric and magnetic fields can both drive the hole spin resonance where the two fields have valley-dependent interference, making an interplay between the spin and valley as information carriers possible for potential valley-spintronic applications. We show how to realize quantum gates on the spin qubit controlled by the valley bit.

  8. Insulator to correlated metal transition in V_1-xMo_xO_2

    SciTech Connect (OSTI)

    Klimczuk, Tomasz; Ronning, Filip; Holman, Katherine; Mcqueen, Tyrel M; Williams, Anthony J; Stephens, P W; Zandbergen, Henny W; Xu, Q; Cava, Robert J

    2009-01-01

    The change from metallic to insulating states is one of the most dramatic transitions that solids undergo on cooling or chemical doping. Many materials display this transition, but only a handful have the right combination of crystal structure and physical properties to serve as model systems. VO{sub 2} is one of those materials. Using Mo as a chemical dopant in VO{sub 2}, we find unanticipated phenomenology for both the electronic and structural characteristics of the resulting insulator to metal transition. The results support a complex, previously proposed scenario involving the coexistence of both electron repulsion and electron pairing for yielding an insulator in VO{sub 2}, but not simply; many issues are raised about local versus itinerant behavior and structure-property correlations in this most iconic ofdoped correlated electron systems.

  9. Structural Flexibility and Alloying in Ultrathin Transition-Metal Chalcogenide Nanowires

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Lin, Junhao; Zhang, Yuyang; Zhou, Wu; Pantelides, Sokrates T.

    2016-01-18

    Metallic transition-metal chalcogenide (TMC) nanowires are an important building block for 2D electronics that may be fabricated within semiconducting transition-metal dichalcogenide (TMDC) monolayers. Tuning the geometric structure and electronic properties of such nanowires is a promising way to pattern diverse functional channels for wiring multiple units inside a 2D electronic circuit. Nevertheless, few experimental investigations have been reported exploring the structural and compositional tunability of these nanowires, due to difficulties in manipulating the structure and chemical composition of an individual nanowire. Here, using a combination of scanning transmission electron microscopy (STEM) and density functional theory (DFT), we report that TMCmore » nanowires have substantial intrinsic structural flexibility and their chemical composition can be manipulated.« less

  10. Transition metal-catalyzed process for addition of amines to carbon-carbon double bonds

    DOE Patents [OSTI]

    Hartwig, John F. (Durham, CT); Kawatsura, Motoi (Chatham, NJ); Loeber, Oliver (New Haven, CT)

    2002-01-01

    The present invention is directed to a process for addition of amines to carbon-carbon double bonds in a substrate, comprising: reacting an amine with a compound containing at least one carbon-carbon double bond in the presence a transition metal catalyst under reaction conditions effective to form a product having a covalent bond between the amine and a carbon atom of the former carbon-carbon double bond. The transition metal catalyst comprises a Group 8 metal and a ligand containing one or more 2-electron donor atoms. The present invention is also directed to enantioselective reactions of amine compounds with compounds containing carbon-carbon double bonds, and a calorimetric assay to evaluate potential catalysts in these reactions.

  11. Heterojunction metal-oxide-metal Au-Fe{sub 3}O{sub 4}-Au single nanowire device for spintronics

    SciTech Connect (OSTI)

    Reddy, K. M. Punnoose, Alex; Hanna, Charles; Padture, Nitin P.

    2015-05-07

    In this report, we present the synthesis of heterojunction magnetite nanowires in alumina template and describe magnetic and electrical properties from a single nanowire device for spintronics applications. Heterojunction Au-Fe-Au nanowire arrays were electrodeposited in porous aluminum oxide templates, and an extensive and controlled heat treatment process converted Fe segment to nanocrystalline cubic magnetite phase with well-defined Au-Fe{sub 3}O{sub 4} interfaces as confirmed by the transmission electron microscopy. Magnetic measurements revealed Verwey transition shoulder around 120 K and a room temperature coercive field of 90 Oe. Current–voltage (I-V) characteristics of a single Au-Fe{sub 3}O{sub 4}-Au nanowire have exhibited Ohmic behavior. Anomalous positive magnetoresistance of about 0.5% is observed on a single nanowire, which is attributed to the high spin polarization in nanowire device with pure Fe{sub 3}O{sub 4} phase and nanocontact barrier. This work demonstrates the ability to preserve the pristine Fe{sub 3}O{sub 4} and well defined electrode contact metal (Au)–magnetite interface, which helps in attaining high spin polarized current.

  12. Regenerable MgO promoted metal oxide oxygen carriers for chemical looping combustion

    DOE Patents [OSTI]

    Siriwardane, Ranjani V.; Miller, Duane D.

    2014-08-19

    The disclosure provides an oxygen carrier comprised of a plurality of metal oxide particles in contact with a plurality of MgO promoter particles. The MgO promoter particles increase the reaction rate and oxygen utilization of the metal oxide when contacting with a gaseous hydrocarbon at a temperature greater than about 725.degree. C. The promoted oxide solid is generally comprised of less than about 25 wt. % MgO, and may be prepared by physical mixing, incipient wetness impregnation, or other methods known in the art. The oxygen carrier exhibits a crystalline structure of the metal oxide and a crystalline structure of MgO under XRD crystallography, and retains these crystalline structures over subsequent redox cycles. In an embodiment, the metal oxide is Fe.sub.2O.sub.3, and the gaseous hydrocarbon is comprised of methane.

  13. Method for heat treating and sintering metal oxides with microwave radiation

    DOE Patents [OSTI]

    Holcombe, Cressie E. (Farragut, TN); Dykes, Norman L. (Oak Ridge, TN); Meek, Thomas T. (Knoxville, TN)

    1989-01-01

    A method for microwave sintering materials, primarily metal oxides, is described. Metal oxides do not normally absorb microwave radiation at temperatures ranging from about room temperature to several hundred degrees centrigrade are sintered with microwave radiation without the use of the heretofore required sintering aids. This sintering is achieved by enclosing a compact of the oxide material in a housing or capsule formed of a oxide which has microwave coupling properties at room temprature up to at least the microwave coupling temperature of the oxide material forming the compact. The heating of the housing effects the initial heating of the oxide material forming the compact by heat transference and then functions as a thermal insulator for the encased oxide material after the oxide material reaches a sufficient temperature to adequately absorb or couple with microwave radiation for heating thereof to sintering temperature.

  14. Extrusion of metal oxide superconducting wire, tube or ribbon

    DOE Patents [OSTI]

    Dusek, Joseph T. (Lombard, IL)

    1993-01-01

    A process for extruding a superconducting metal oxide composition YBa.sub.2 Cu.sub.3 O.sub.7-x provides a wire (tube or ribbon) having a cohesive mass and a degree of flexibility together with enhanced electrical properties. Wire diameters in the range of 6-85 mils have been produced with smaller wires on the order of 10 mils in diameter exhibiting enhanced flexibility for forming braided, or multistrand, configurations for greater current carrying capacity. The composition for extrusion contains a polymeric binder to provide a cohesive mass to bind the particles together during the extrusion process with the binder subsequently removed at lower temperatures during sintering. The composition for extrusion further includes a deflocculent, an organic plasticizer and a solvent which also are subsequently removed during sintering. Electrically conductive tubing with an inner diameter of 52 mil and an outer diameter of 87-355 mil has also been produced. Flat ribbons have been produced in the range of 10-125 mil thick by 100-500 mil wide. The superconducting wire, tube or ribbon may include an outer ceramic insulating sheath co-extruded with the wire, tubing or ribbon.

  15. Extrusion of metal oxide superconducting wire, tube or ribbon

    DOE Patents [OSTI]

    Dusek, Joseph T.

    1993-10-05

    A process for extruding a superconducting metal oxide composition YBa.sub.2 Cu.sub.3 O.sub.7-x provides a wire (tube or ribbon) having a cohesive mass and a degree of flexibility together with enhanced electrical properties. Wire diameters in the range of 6-85 mils have been produced with smaller wires on the order of 10 mils in diameter exhibiting enhanced flexibility for forming braided, or multistrand, configurations for greater current carrying capacity. The composition for extrusion contains a polymeric binder to provide a cohesive mass to bind the particles together during the extrusion process with the binder subsequently removed at lower temperatures during sintering. The composition for extrusion further includes a deflocculent, an organic plasticizer and a solvent which also are subsequently removed during sintering. Electrically conductive tubing with an inner diameter of 52 mil and an outer diameter of 87-355 mil has also been produced. Flat ribbons have been produced in the range of 10-125 mil thick by 100-500 mil wide. The superconducting wire, tube or ribbon may include an outer ceramic insulating sheath co-extruded with the wire, tubing or ribbon.

  16. Production of crystalline refractory metal oxides containing colloidal metal precipitates and useful as solar-effective absorbers

    DOE Patents [OSTI]

    Narayan, Jagdish (Knoxville, TN); Chen, Yok (Oak Ridge, TN)

    1983-01-01

    This invention is a new process for producing refractory crystalline oxides having improved or unusual properties. The process comprises the steps of forming a doped-metal crystal of the oxide; exposing the doped crystal in a bomb to a reducing atmosphere at superatmospheric pressure and a temperature effecting precipitation of the dopant metal in the crystal lattice of the oxide but insufficient to effect net diffusion of the metal out of the lattice; and then cooling the crystal. Preferably, the cooling step is effected by quenching. The process forms colloidal precipitates of the metal in the oxide lattice. The process may be used, for example, to produce thermally stable black MgO crystalline bodies containing magnetic colloidal precipitates consisting of about 99% Ni. The Ni-containing bodies are solar-selective absorbers, having a room-temperature absorptivity of about 0.96 over virtually all of the solar-energy spectrum and exhibiting an absorption edge in the region of 2 .mu.m. The process parameters can be varied to control the average size of the precipitates. The process can produce a black MgO crystalline body containing colloidal Ni precipitates, some of which have the face-centered-cubic structure and others of which have the body-centered cubic structure. The products of the process are metal-precipitate-containing refractory crystalline oxides which have improved or unique optical, mechanical, magnetic, and/or electronic properties.

  17. Thermal Conductivity and Thermopower near the 2D Metal-Insulator transition, Final Technical Report

    SciTech Connect (OSTI)

    SARACHIK, MYRIAM P

    2015-02-20

    STUDIES OF STRONGLY-INTERACTING 2D ELECTRON SYSTEMS There is a great deal of current interest in the properties of systems in which the interaction between electrons (their potential energy) is large compared to their kinetic energy. We have investigated an apparent, unexpected metal-insulator transition inferred from the behavior of the temperature-dependence of the resistivity; moreover, detailed analysis of the behavior of the magnetoresistance suggests that the electrons effective mass diverges, supporting this scenario. Whether this is a true phase transition or crossover behavior has been strenuously debated over the past 20 years. Our measurements have now shown that the thermoelectric power of these 2D materials diverges at a finite density, providing clear evidence that this is, in fact, a phase transition to a new low-density phase which may be a precursor or a direct transition to the long sought-after electronic crystal predicted by Eugene Wigner in 1934.

  18. Thermally driven analog of the Barkhausen effect at the metal-insulator transition in vanadium dioxide

    SciTech Connect (OSTI)

    Huber-Rodriguez, Benjamin; Ji, Heng; Chen, Chih-Wei [Department of Physics and Astronomy, Rice University, Houston, Texas 77005 (United States); Kwang, Siu Yi [Department of Physics, National University of Singapore, Singapore 117551 (Singapore); Hardy, Will J. [Applied Physics Program, Rice Quantum Institute, Rice University, Houston, Texas 77005 (United States); Morosan, Emilia [Department of Physics and Astronomy, Rice University, Houston, Texas 77005 (United States); Department of Chemistry, Rice University, Houston, Texas 77005 (United States); Department of Materials Science and Nanoengineering, Rice University, Houston, Texas 77005 (United States); Natelson, Douglas [Department of Physics and Astronomy, Rice University, Houston, Texas 77005 (United States); Department of Materials Science and Nanoengineering, Rice University, Houston, Texas 77005 (United States); Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005 (United States)

    2014-09-29

    The physics of the metal-insulator transition (MIT) in vanadium dioxide remains a subject of intense interest. Because of the complicating effects of elastic strain on the phase transition, there is interest in comparatively strain-free means of examining VO{sub 2} material properties. We report contact-free, low-strain studies of the MIT through an inductive bridge approach sensitive to the magnetic response of VO{sub 2} powder. Rather than observing the expected step-like change in susceptibility at the transition, we argue that the measured response is dominated by an analog of the Barkhausen effect, due to the extremely sharp jump in the magnetic response of each grain as a function of time as the material is cycled across the phase boundary. This effect suggests that future measurements could access the dynamics of this and similar phase transitions.

  19. Electronically conductive ceramics for high temperature oxidizing environments

    DOE Patents [OSTI]

    Kucera, Gene H. (Downers Grove, IL); Smith, James L. (Lemont, IL); Sim, James W. (Evergreen Park, IL)

    1986-01-01

    A high temperature, ceramic composition having electronic conductivity as measured by resistivity below about 500 ohm-cm, chemical stability particularly with respect to cathode conditions in a molten carbonate fuel cell, and composed of an alkali metal, transition metal oxide containing a dopant metal in the crystalline structure to replace a portion of the alkali metal or transition metal.

  20. Reactivity of biogenic manganese oxide for metal sequestration and photochemistry: Computational solid state physics study

    SciTech Connect (OSTI)

    Kwon, K.D.; Sposito, G.

    2010-02-01

    Many microbes, including both bacteria and fungi, produce manganese (Mn) oxides by oxidizing soluble Mn(II) to form insoluble Mn(IV) oxide minerals, a kinetically much faster process than abiotic oxidation. These biogenic Mn oxides drive the Mn cycle, coupling it with diverse biogeochemical cycles and determining the bioavailability of environmental contaminants, mainly through strong adsorption and redox reactions. This mini review introduces recent findings based on quantum mechanical density functional theory that reveal the detailed mechanisms of toxic metal adsorption at Mn oxide surfaces and the remarkable role of Mn vacancies in the photochemistry of these minerals.

  1. Supersaturating silicon with transition metals by ion implantation and pulsed laser melting

    SciTech Connect (OSTI)

    Recht, Daniel; Aziz, Michael J.; Smith, Matthew J.; Grade?ak, Silvija; Charnvanichborikarn, Supakit; Williams, James S.; Sullivan, Joseph T.; Winkler, Mark T.; Buonassisi, Tonio; Mathews, Jay; Warrender, Jeffrey M.

    2013-09-28

    We investigate the possibility of creating an intermediate band semiconductor by supersaturating Si with a range of transition metals (Au, Co, Cr, Cu, Fe, Pd, Pt, W, and Zn) using ion implantation followed by pulsed laser melting (PLM). Structural characterization shows evidence of either surface segregation or cellular breakdown in all transition metals investigated, preventing the formation of high supersaturations. However, concentration-depth profiling reveals that regions of Si supersaturated with Au and Zn are formed below the regions of cellular breakdown. Fits to the concentration-depth profile are used to estimate the diffusive speeds, v{sub D,} of Au and Zn, and put lower bounds on v{sub D} of the other metals ranging from 10{sup 2} to 10{sup 4} m/s. Knowledge of v{sub D} is used to tailor the irradiation conditions and synthesize single-crystal Si supersaturated with 10{sup 19} Au/cm{sup 3} without cellular breakdown. Values of v{sub D} are compared to those for other elements in Si. Two independent thermophysical properties, the solute diffusivity at the melting temperature, D{sub s}(T{sub m}), and the equilibrium partition coefficient, k{sub e}, are shown to simultaneously affect v{sub D}. We demonstrate a correlation between v{sub D} and the ratio D{sub s}(T{sub m})/k{sub e}{sup 0.67}, which is exhibited for Group III, IV, and V solutes but not for the transition metals investigated. Nevertheless, comparison with experimental results suggests that D{sub s}(T{sub m})/k{sub e}{sup 0.67} might serve as a metric for evaluating the potential to supersaturate Si with transition metals by PLM.

  2. Method for the rapid synthesis of large quantities of metal oxide nanowires at low temperatures

    DOE Patents [OSTI]

    Sunkara, Mahendra Kumar (Louisville, KY); Vaddiraju, Sreeram (Mountain View, CA); Mozetic, Miran (Ljubljan, SI); Cvelbar, Uros (Idrija, SI)

    2009-09-22

    A process for the rapid synthesis of metal oxide nanoparticles at low temperatures and methods which facilitate the fabrication of long metal oxide nanowires. The method is based on treatment of metals with oxygen plasma. Using oxygen plasma at low temperatures allows for rapid growth unlike other synthesis methods where nanomaterials take a long time to grow. Density of neutral oxygen atoms in plasma is a controlling factor for the yield of nanowires. The oxygen atom density window differs for different materials. By selecting the optimal oxygen atom density for various materials the yield can be maximized for nanowire synthesis of the metal.

  3. Characterization of a Fe/Y{sub 2}O{sub 3} metal/oxide interface using neutron and x-ray scattering

    SciTech Connect (OSTI)

    Watkins, E. B.; Majewski, J. E-mail: jarek@lanl.gov; Kashinath, A.; Wang, P.; Baldwin, J. K.; Demkowicz, M. J. E-mail: jarek@lanl.gov

    2014-07-28

    The structure of metal/oxide interfaces is important to the radiation resistance of oxide dispersion-strengthened steels. We find evidence of gradual variations in stoichiometry and magnetization across a Fe/Y{sub 2}O{sub 3} metal/oxide heterophase interface using neutron and x-ray reflectometry. These findings suggest that the Fe/Y{sub 2}O{sub 3} interface is a transitional zone approximately ?64?-thick containing mixtures or compounds of Fe, Y, and O. Our results illustrate the complex chemical and magnetic nature of Fe/oxide interfaces and demonstrate the utility of combined neutron and x-ray techniques as tools for characterizing them.

  4. Long-term research in Japan: amorphous metals, metal oxide varistors, high-power semiconductors and superconducting generators

    SciTech Connect (OSTI)

    Hane, G.J.; Yorozu, M.; Sogabe, T.; Suzuki, S.

    1985-04-01

    The review revealed that significant activity is under way in the research of amorphous metals, but that little fundamental work is being pursued on metal oxide varistors and high-power semiconductors. Also, the investigation of long-term research program plans for superconducting generators reveals that activity is at a low level, pending the recommendations of a study currently being conducted through Japan's Central Electric Power Council.

  5. Oxidation/Reduction Reactions at the Metal Contact-TlBr Interface...

    Office of Scientific and Technical Information (OSTI)

    Title: OxidationReduction Reactions at the Metal Contact-TlBr Interface: An X-ray Photoelectron Spectroscopy Study Authors: Nelson, A J ; Swanberg, E L ; Voss, L F ; Graff, R T ; ...

  6. Revealing the True Nature of a Metal Oxide | The Ames Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Revealing the True Nature of a Metal Oxide Extensive calculations revealed that the calcium-iridium-oxygen compound CaIrO3 is a Slater-type insulator, putting to rest the debate of...

  7. Oxidation/Reduction Reactions at the Metal Contact-TlBr Interface...

    Office of Scientific and Technical Information (OSTI)

    Reduction Reactions at the Metal Contact-TlBr Interface: An X-ray Photoelectron Spectroscopy Study Citation Details In-Document Search Title: OxidationReduction Reactions at...

  8. Thermal and Physical Properties of Plutonium Dioxide Produced from the Oxidation of Metal: a Data Summary

    SciTech Connect (OSTI)

    Wayne, David M.

    2014-01-13

    The ARIES Program at the Los Alamos National Laboratory removes plutonium metal from decommissioned nuclear weapons, and converts it to plutonium dioxide in a specially-designed Direct Metal Oxidation furnace. The plutonium dioxide is analyzed for specific surface area, particle size distribution, and moisture content. The purpose of these analyses is to certify that the plutonium dioxide powder meets or exceeds the specifications of the end-user, and the specifications for the packaging and transport of nuclear materials. Analytical results from plutonium dioxide from ARIES development activities, from ARIES production activities, from muffle furnace oxidation of metal, and from metal that was oxidized over a lengthy time interval in air at room temperature, are presented. The processes studied produce plutonium dioxide powder with distinct differences in measured properties, indicating the significant influence of oxidation conditions on physical properties.

  9. Systematic prediction of high-pressure melting curves of transition metals

    SciTech Connect (OSTI)

    Hieu, Ho Khac, E-mail: hieuhk@duytan.edu.vn [Institute of Research and Development, Duy Tan University, K7/25 Quang Trung, Danang (Viet Nam)

    2014-10-28

    The pressure effects on melting temperatures of transition metals have been studied based on the combination of the modified Lindemann criterion with statistical moment method in quantum statistical mechanics. Numerical calculations have been performed for five transition metals including Cu, Pd, Pt, Ni, and Mn up to pressure 100?GPa. Our results are in good and reasonable agreements with available experimental data. This approach gives us a relatively simple method for qualitatively calculating high-pressure melting temperature. Moreover, it can be used to verify future experimental and theoretical works. This research proposes the potential of the combination of statistical moment method and the modified Lindemann criterion on predicting high-pressure melting of materials.

  10. Metal to Insulator Transition on the N = 0 Landau Level in Graphene

    SciTech Connect (OSTI)

    Zhang, L.; Zhang, Y.; Khodas, M.; Valla, T.; Zaliznyak, I.A.

    2010-07-23

    The magnetotransport in single layer graphene has been experimentally investigated in magnetic fields up to 18 T as a function of temperature. A pronounced T dependence is observed for T {approx}< 50 K, which is either metallic, or insulating, depending on the filling factor {nu}. The metal-insulator transition (MIT) occurs at |{nu}{sub c}| {approx}0.65 and in the regime of the dissipative transport, where the longitudinal resistance R{sub xx} >1/2R{sub K}. The critical resistivity (R{sub xx} per square) is {rho}{sub xx}({nu}{sub c}) {approx} 1/2R{sub K} and is correlated with the appearance of zero plateau in Hall conductivity {sigma}{sub xy}({nu}) and peaks in {sigma}{sub xx}({nu}). This leads us to construct a universal low-T (n, B) phase diagram of this quantum phase transition.

  11. Structure and magnetism of epitaxial rare-earth-transition-metal films

    SciTech Connect (OSTI)

    Fullerton, E.E.; Sowers, C.H.; Pearson, J.P.; Bader, S.D.

    1996-10-01

    Growth of epitaxial transition-metal superlattices; has proven essential in elucidating the role of crystal orientation and structure on magnetic properties such as giant magnetoresistance, interlayer coupling, and magnetic surface anisotropies. Extending these studies to the growth of epitaxial rare earth-transition metal (RE-TM) films and superlattices promises to play an equally important role in exploring and optimizing the properties of hard magnets. For instance, Skomski and Coey predict that a giant energy product (120 MG Oe) is possible in multilayer structures consisting of aligned hard-magnet layers exchanged coupled with soft-phase layers with high magnetization. Epitaxy provides one route to synthesizing such exchange-hardened magnets on controlled length scales. Epitaxial growth also allows the magnetic properties to be tailored by controlling the crystal orientation and the anisotropies of the magnetic layers and holds the possibility of stabilizing metastable phases. This paper describes the epitaxy and magnetic properties for several alloys.

  12. Beyond the Lone-Pair Model for Structurally Distorted Metal Oxides

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Beyond the Lone-Pair Model for Structurally Distorted Metal Oxides Print "Ferroelectricity," by analogy to ferromagnetism, is defined as the presence of spontaneous electrical polarization in a material, often arising from distortions in the material's crystal structure. In oxides of the metals lead and bismuth, such distortions were for many years attributed to the existence of "lone pair" electrons: pairs of chemically inert, nonbonding valence electrons in hybrid orbitals

  13. Beyond the Lone-Pair Model for Structurally Distorted Metal Oxides

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Beyond the Lone-Pair Model for Structurally Distorted Metal Oxides Print "Ferroelectricity," by analogy to ferromagnetism, is defined as the presence of spontaneous electrical polarization in a material, often arising from distortions in the material's crystal structure. In oxides of the metals lead and bismuth, such distortions were for many years attributed to the existence of "lone pair" electrons: pairs of chemically inert, nonbonding valence electrons in hybrid orbitals

  14. Additional capacities seen in metal oxide lithium-ion battery electrodes

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | SciTech Connect SciTech Connect Search Results Journal Article: Additional capacities seen in metal oxide lithium-ion battery electrodes Citation Details In-Document Search Title: Additional capacities seen in metal oxide lithium-ion battery electrodes Authors: Hu, Yan-Yan ; Liu, Zigeng ; Nam, Kyung-Wan ; Borkiewicz, Olaf ; Cheng, Jun ; Hua, Xiao ; Dunstan, Matthew ; Yu, Xiqian ; Wiaderek, Kamila ; Du, Lin-Shu ; Chapman, Karena W. ; Chupas, Peter J. ; Yang, Xiao-Qing ;

  15. Beyond the Lone-Pair Model for Structurally Distorted Metal Oxides

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Beyond the Lone-Pair Model for Structurally Distorted Metal Oxides Print "Ferroelectricity," by analogy to ferromagnetism, is defined as the presence of spontaneous electrical polarization in a material, often arising from distortions in the material's crystal structure. In oxides of the metals lead and bismuth, such distortions were for many years attributed to the existence of "lone pair" electrons: pairs of chemically inert, nonbonding valence electrons in hybrid orbitals

  16. Spillover-Assisted Hydrogen Evolution at Si-based Metal-Oxide-Semiconductor

    Office of Scientific and Technical Information (OSTI)

    Photoelectrodes. (Journal Article) | SciTech Connect Spillover-Assisted Hydrogen Evolution at Si-based Metal-Oxide-Semiconductor Photoelectrodes. Citation Details In-Document Search Title: Spillover-Assisted Hydrogen Evolution at Si-based Metal-Oxide-Semiconductor Photoelectrodes. Authors: Talin, Albert Alec ; Esposito, Daniel V. ; Levin, Igor ; Moffat, Thomas P. Publication Date: 2012-12-01 OSTI Identifier: 1063415 Report Number(s): SAND2012-10868J DOE Contract Number: AC04-94AL85000

  17. Thermochemical cycle of a mixed metal oxide for augmentation of thermal

    Office of Scientific and Technical Information (OSTI)

    energy storage in solid particles. (Conference) | SciTech Connect Thermochemical cycle of a mixed metal oxide for augmentation of thermal energy storage in solid particles. Citation Details In-Document Search Title: Thermochemical cycle of a mixed metal oxide for augmentation of thermal energy storage in solid particles. Abstract not provided. Authors: Ehrhart, Brian David ; Coker, Eric Nicholas ; Siegel, Nathan Phillip ; Weimer, Alan Wesley. Publication Date: 2013-06-01 OSTI Identifier:

  18. Peculiarities of the electron spectrum and metal-insulator transition in the strong correlation limit

    SciTech Connect (OSTI)

    Irkhin, V. Yu. Zarubin, A. V.

    2013-05-15

    Green's function in the paramagnetic phase of the Hubbard model with strong electron correlations is calculated by the many-electron operators method. The density of states pattern is considered in the case of half-filling (metal-insulator transition) and in the doped case. The effect of the low-temperature Kondo scattering on the energy spectrum is analyzed, and the results are compared with the results of the dynamical mean-field theory (DMFT).

  19. Insulator-to-Metal Transition of Vanadium Dioxide | U.S. DOE Office of

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science (SC) Insulator-to-Metal Transition of Vanadium Dioxide Advanced Scientific Computing Research (ASCR) ASCR Home About Research Facilities Science Highlights Benefits of ASCR Funding Opportunities Advanced Scientific Computing Advisory Committee (ASCAC) Community Resources Contact Information Advanced Scientific Computing Research U.S. Department of Energy SC-21/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-7486 F: (301) 903-4846 E: Email Us More

  20. Calculation of binary phase diagrams between the actinide elements, rare earth elements, and transition metal elements

    SciTech Connect (OSTI)

    Selle, J E

    1992-06-26

    Attempts were made to apply the Kaufman method of calculating binary phase diagrams to the calculation of binary phase diagrams between the rare earths, actinides, and the refractory transition metals. Difficulties were encountered in applying the method to the rare earths and actinides, and modifications were necessary to provide accurate representation of known diagrams. To calculate the interaction parameters for rare earth-rare earth diagrams, it was necessary to use the atomic volumes for each of the phases: liquid, body-centered cubic, hexagonal close-packed, and face-centered cubic. Determination of the atomic volumes of each of these phases for each element is discussed in detail. In some cases, empirical means were necessary. Results are presented on the calculation of rare earth-rare earth, rare earth-actinide, and actinide-actinide diagrams. For rare earth-refractory transition metal diagrams and actinide-refractory transition metal diagrams, empirical means were required to develop values for the enthalpy of vaporization for rare earth elements and values for the constant (C) required when intermediate phases are present. Results of using the values determined for each element are presented.

  1. Pressure induced metallization with absence of structural transition in layered molybdenum diselenide

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhao, Zhao; Zhang, Haijun; Yuan, Hongtao; Wang, Shibing; Lin, Yu; Zeng, Qiaoshi; Xu, Gang; Liu, Zhenxian; Solanki, G. K.; Patel, K. D.; et al

    2015-06-19

    Layered transition-metal dichalcogenides have emerged as exciting material systems with atomically thin geometries and unique electronic properties. Pressure is a powerful tool for continuously tuning their crystal and electronic structures away from the pristine states. Here, we systematically investigated the pressurized behavior of MoSe2 up to ~60 GPa using multiple experimental techniques and ab-initio calculations. MoSe2 evolves from an anisotropic two-dimensional layered network to a three-dimensional structure without a structural transition, which is a complete contrast to MoS2. The role of the chalcogenide anions in stabilizing different layered patterns is underscored by our layer sliding calculations. MoSe2 possesses highly tunablemore » transport properties under pressure, determined by the gradual narrowing of its band-gap followed by metallization. The continuous tuning of its electronic structure and band-gap in the range of visible light to infrared suggest possible energy-variable optoelectronics applications in pressurized transition-metal dichalcogenides.« less

  2. Effect of hydrothermal condition on the formation of multi-component oxides of Ni-based metallic glass under high temperature water near the critical point

    SciTech Connect (OSTI)

    Kim, J. S.; Kim, S. Y.; Kim, D. H.; Ott, R. T.; Kim, H. G.; Lee, M. H.

    2015-07-01

    The specific feature of multi-component oxides synthesized by hydrothermal process under high temperature (633 K) and highly pressurized water (18.9 MPa) near critical point. Effects of hydrothermal processing duration times 24 hours and 72 hours, respectively, on the oxide formation of the Ni59Zr20Ti16Si2Sn3 metallic glass synthesized by powder metallurgy process were characterized by X-ray diffractometer, differential scanning calorimeter along with the particle size, morphology and crystalline phase of the oxides. The crystallization of the needle-shape NiTiO3, ZrTiO4 and ZrSnO4 ternary oxide phases observed on the surface of metallic glass at below glass transition temperature and the morphology of oxide phases changed to plate-shape around 2 ?m in diameter by the increase processing time. This hydrothermal processing in subcritical water provides accelerated dense metal oxide crystals due to the reaction medium being at higher pressure than conventional oxidation processing.

  3. Effect of hydrothermal condition on the formation of multi-component oxides of Ni-based metallic glass under high temperature water near the critical point

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kim, J. S.; Kim, S. Y.; Kim, D. H.; Ott, R. T.; Kim, H. G.; Lee, M. H.

    2015-07-01

    The specific feature of multi-component oxides synthesized by hydrothermal process under high temperature (633 K) and highly pressurized water (18.9 MPa) near critical point. Effects of hydrothermal processing duration times 24 hours and 72 hours, respectively, on the oxide formation of the Ni59Zr20Ti16Si2Sn3 metallic glass synthesized by powder metallurgy process were characterized by X-ray diffractometer, differential scanning calorimeter along with the particle size, morphology and crystalline phase of the oxides. The crystallization of the needle-shape NiTiO3, ZrTiO4 and ZrSnO4 ternary oxide phases observed on the surface of metallic glass at below glass transition temperature and the morphology of oxide phasesmore » changed to plate-shape around 2 μm in diameter by the increase processing time. This hydrothermal processing in subcritical water provides accelerated dense metal oxide crystals due to the reaction medium being at higher pressure than conventional oxidation processing.« less

  4. Thermodynamic Investigations of Lithium- and Manganese-Rich Transition

    Energy Savers [EERE]

    Metal Oxides | Department of Energy Thermodynamic Investigations of Lithium- and Manganese-Rich Transition Metal Oxides Thermodynamic Investigations of Lithium- and Manganese-Rich Transition Metal Oxides 2013 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting PDF icon es192_lu_2013_p.pdf More Documents & Publications Vehicle Technologies Office Merit Review 2014: Electrochemical Modeling of LMR-NMC Materials and Electrodes

  5. Effective alkaline metal-catalyzed oxidative delignification of hybrid poplar

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Bhalla, Aditya; Bansal, Namita; Stoklosa, Ryan J.; Fountain, Mackenzie; Ralph, John; Hodge, David B.; Hegg, Eric L.

    2016-02-09

    Background: Strategies to improve copper-catalyzed alkaline hydrogen peroxide (Cu-AHP) pretreatment of hybrid poplar were investigated. These improvements included a combination of increasing hydrolysis yields, while simultaneously decreasing process inputs through (i) more efficient utilization of H2O2 and (ii) the addition of an alkaline extraction step prior to the metal-catalyzed AHP pretreatment. We hypothesized that utilizing this improved process could substantially lower the chemical inputs needed during pretreatment. Results: Hybrid poplar was pretreated utilizing a modified process in which an alkaline extraction step was incorporated prior to the Cu-AHP treatment step and H2O2 was added batch-wise over the course of 10more » h. Our results revealed that the alkaline pre-extraction step improved both lignin and xylan solubilization, which ultimately led to improved glucose (86 %) and xylose (95 %) yields following enzymatic hydrolysis. An increase in the lignin solubilization was also observed with fed-batch H2O2 addition relative to batch-only addition, which again resulted in increased glucose and xylose yields (77 and 93 % versus 63 and 74 %, respectively). Importantly, combining these strategies led to significantly improved sugar yields (96 % glucose and 94 % xylose) following enzymatic hydrolysis. In addition, we found that we could substantially lower the chemical inputs (enzyme, H2O2, and catalyst), while still maintaining high product yields utilizing the improved Cu-AHP process. This pretreatment also provided a relatively pure lignin stream consisting of ≥90 % Klason lignin and only 3 % xylan and 2 % ash following precipitation. Two-dimensional heteronuclear single-quantum coherence (2D HSQC) NMR and size-exclusion chromatography demonstrated that the solubilized lignin was high molecular weight (Mw ≈ 22,000 Da) and only slightly oxidized relative to lignin from untreated poplar. In conclusion: This study demonstrated that the fed-batch, two-stage Cu-AHP pretreatment process was effective in pretreating hybrid poplar for its conversion into fermentable sugars. Results showed sugar yields near the theoretical maximum were achieved from enzymatically hydrolyzed hybrid poplar by incorporating an alkaline extraction step prior to pretreatment and by efficiently utilizing H2O2 during the Cu-AHP process. Significantly, this study reports high sugar yields from woody biomass treated with an AHP pretreatment under mild reaction conditions.« less

  6. Porous desulfurization sorbent pellets containing a reactive metal oxide and an inert zirconium compound

    SciTech Connect (OSTI)

    Gardner, Todd H.; Gasper-Galvin, Lee D.

    1996-12-01

    Sorbent pellets for removing hydrogen sulfide from coal gas are prepared by combining a reactive oxide, in particular zinc oxide, with a zirconium compound such as an oxide, silicate, or aluminate of zirconium, and an inorganic binder and pelletizing and calcining the mixture. Alternately, the zinc oxide may be replaced by copper oxide or a combination of copper, molybdenum, and manganese oxides. The pellet components may be mixed in dry form, moistened to produce a paste, and converted to pellets by forming an aqueous slurry of the components and spray drying the slurry, or the reactive oxide may be formed on existing zirconium-containing catalyst-carrier pellets by infusing a solution of a salt of the active metal onto the existing pellets and firing at a high temperature to produce the oxide. Pellets made according to this invention show a high reactivity with hydrogen sulfide and durability such as to be useful over repeated cycles of sorption and regeneration.

  7. NREL Demonstrates Efficient Solar Water Splitting by Metal Oxide...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    energy sources. Production of O 2 is the only scalable and renewable oxidation that can balance these fuel-forming reduction reactions. However, few materials have the necessary...

  8. Synthesis of high T.sub.C superconducting coatings and patterns by melt writing and oxidation of metallic precursor alloys

    DOE Patents [OSTI]

    Gao, Wei (Somerville, MA); Vander Sande, John B. (Newbury, MA)

    1998-01-01

    A method is provided for fabrication of superconducting oxides and superconducting oxide composites and for joining superconductors to other materials. A coating of a molten alloy containing the metallic elements of the oxide is applied to a substrate surface and oxidized to form the superconducting oxide. A material can be contacted to the molten alloy which is subsequently oxidized joining the material to the resulting superconducting oxide coating. Substrates of varied composition and shape can be coated or joined by this method.

  9. Observation of complete space-charge-limited transport in metal-oxide-graphene heterostructure

    SciTech Connect (OSTI)

    Chen, Wei; Wang, Fei; Fang, Jingyue; Wang, Guang; Qin, Shiqiao; Zhang, Xue-Ao E-mail: xazhang@nudt.edu.cn; Wang, Chaocheng; Wang, Li E-mail: xazhang@nudt.edu.cn

    2015-01-12

    The metal-oxide-graphene heterostructures have abundant physical connotations. As one of the most important physical properties, the electric transport property of the gold-chromium oxide-graphene heterostructure has been studied. The experimental measurement shows that the conductive mechanism is dominated by the space-charge-limited transport, a kind of bulk transport of an insulator with charge traps. Combining the theoretical analysis, some key parameters such as the carrier mobility and trap energy also are obtained. The study of the characteristics of the metal-oxide-graphene heterostructures is helpful to investigate the graphene-based electronic and photoelectric devices.

  10. Ultra-low contact resistance at an epitaxial metal/oxide heterojunction through interstitial site doping

    SciTech Connect (OSTI)

    Chambers, Scott A.; Gu, Meng; Sushko, Petr V.; Yang, Hao; Wang, Chong M.; Browning, Nigel D.

    2013-08-07

    The ability to form reliable, low-resistance Ohmic contacts is of critical importance to the ongoing development of oxide electronics. Most metals form Schottky barriers when deposited on oxide surfaces. Ohmic contacts rarely occur, and the associated contact resistances are not particularly low. Little is known at an atomistic level about what leads to a good Ohmic contact on a wide-gap oxide. Here we describe the structure of a simple, yet exceptionally low-contact resistance Ohmic metal on an important oxide semiconductor -- epitaxial Cr on Nb-doped SrTiO3(001). Heteroepitaxial growth is accompanied by Cr diffusion into the STO and occupation of interstitial sites within the first few atomic planes. Interstitial Cr is ionized and the resulting electrons occupy the STO conduction band, resulting in effective metallization near the interface.

  11. Electronically conducting metal oxide nanoparticles and films for optical sensing applications

    DOE Patents [OSTI]

    Ohodnicki, Jr., Paul R.; Wang, Congjun; Andio, Mark A

    2014-09-16

    The disclosure relates to a method of detecting a change in a chemical composition by contacting a conducting oxide material with a monitored stream, illuminating the conducting oxide material with incident light, collecting exiting light, monitoring an optical signal based on a comparison of the incident light and the exiting light, and detecting a shift in the optical signal. The conducting metal oxide has a carrier concentration of at least 10.sup.17/cm.sup.3, a bandgap of at least 2 eV, and an electronic conductivity of at least 10.sup.-1 S/cm, where parameters are specified at the gas stream temperature. The optical response of the conducting oxide materials is proposed to result from the high carrier concentration and electronic conductivity of the conducting metal oxide, and the resulting impact of changing gas atmospheres on that relatively high carrier concentration and electronic conductivity. These changes in effective carrier densities and electronic conductivity of conducting metal oxide films and nanoparticles are postulated to be responsible for the change in measured optical absorption associated with free carriers. Exemplary conducting metal oxides include but are not limited to Al-doped ZnO, Sn-doped In.sub.2O.sub.3, Nb-doped TiO.sub.2, and F-doped SnO.sub.2.

  12. Plasmonic transparent conducting metal oxide nanoparticles and films for optical sensing applications

    DOE Patents [OSTI]

    Ohodnicki, Jr., Paul R; Wang, Congjun; Andio, Mark A

    2014-01-28

    The disclosure relates to a method of detecting a change in a chemical composition by contacting a doped oxide material with a monitored stream, illuminating the doped oxide material with incident light, collecting exiting light, monitoring an optical signal based on a comparison of the incident light and the exiting light, and detecting a shift in the optical signal. The doped metal oxide has a carrier concentration of at least 10.sup.18/cm.sup.3, a bandgap of at least 2 eV, and an electronic conductivity of at least 10.sup.1 S/cm, where parameters are specified at a temperature of 25.degree. C. The optical response of the doped oxide materials results from the high carrier concentration of the doped metal oxide, and the resulting impact of changing gas atmospheres on that relatively high carrier concentration. These changes in effective carrier densities of conducting metal oxide nanoparticles are postulated to be responsible for the change in measured optical absorption associated with free carriers. Exemplary doped metal oxides include but are not limited to Al-doped ZnO, Sn-doped In.sub.2O.sub.3, Nb-doped TiO.sub.2, and F-doped SnO.sub.2.

  13. A comparative DFT study of the catalytic activity of the 3d transition metal sulphides surfaces

    SciTech Connect (OSTI)

    Gomez-Balderas, R.; Oviedo-Roa, R; Martinez-Magadan, J M.; Amador, C.; Dixon, David A. )

    2002-10-10

    The catalytic activity of the first transition metal series sulphides for hydrodesulfurization (HDS) reactions exhibits a particular behaviour when analysed as a function of the metal position in the Periodic Table. This work reports a comparative study of the electronic structure of the bulk and of the (0 0 1) metal surface (assumed to be the reactive surface) for the Sc-Zn monosulphides. The systems were modeled using the NiAs prototype crystal structure for the bulk and by applying the supercell model with seven atomic layers for (0 0 1) surfaces. The electronic structure of closed-packed solids code based on the density-functional theory and adopting the muffin-tin approximation to the potential was employed in the calculations of the electronic properties. For the Co and Ni sulphides, the density of states (DOS) variations between the metal atom present in the bulk and the ones exposed at the surface show that at the surface, there exists a higher DOS in the occupied states region just below the Fermi level. This feature might indicate a good performance of these two metal sulphides substrates in the HDS reactions favouring a donation, back-donation mechanism. In contrast, the DOS at the surface of Mn is increased in the unoccupied states region, just above the Fermi level. This suggests the possibility of a strong interaction with charge dontating sulphur adsorbate atoms poisoning the active substrate surface.

  14. Method of nitriding, carburizing, or oxidizing refractory metal articles using microwaves

    DOE Patents [OSTI]

    Holcombe, Cressie E. (Knoxville, TN); Dykes, Norman L. (Oak Ridge, TN); Tiegs, Terry N. (Lenoir City, TN)

    1992-01-01

    A method of nitriding an article of refractory-nitride-forming metal or metalloids. A consolidated metal or metalloid article is placed inside a microwave oven and nitrogen containing gas is introduced into the microwave oven. The metal or metalloid article is heated to a temperature sufficient to react the metal or metalloid with the nitrogen by applying a microwave energy within the microwave oven. The metal or metalloid article is maintained at that temperature for a period of time sufficient to convert the article of metal or metalloid to an article of refractory nitride. in addition, a method of applying a coating, such as a coating of an oxide, a carbide, or a carbo-nitride, to an article of metal or metalloid by microwave heating.

  15. Method of nitriding, carburizing, or oxidizing refractory metal articles using microwaves

    DOE Patents [OSTI]

    Holcombe, C.E.; Dykes, N.L.; Tiegs, T.N.

    1992-10-13

    A method of nitriding an article of refractory-nitride-forming metal or metalloids. A consolidated metal or metalloid article is placed inside a microwave oven and nitrogen containing gas is introduced into the microwave oven. The metal or metalloid article is heated to a temperature sufficient to react the metal or metalloid with the nitrogen by applying a microwave energy within the microwave oven. The metal or metalloid article is maintained at that temperature for a period of time sufficient to convert the article of metal or metalloid to an article of refractory nitride. in addition, a method of applying a coating, such as a coating of an oxide, a carbide, or a carbo-nitride, to an article of metal or metalloid by microwave heating.

  16. Phase transition and possible metallization in CeVO{sub 4} under pressure

    SciTech Connect (OSTI)

    Garg, Alka B.; Shanavas, K.V.; Wani, B.N.; Sharma, Surinder M.

    2013-07-15

    Phase stability of CeVO{sub 4} under pressure has been investigated using synchrotron based angle dispersive x-ray diffraction (ADXRD), electrical resistance and first principles calculations. The results indicate that the ambient zircon structure of the compound transforms to a low symmetry monoclinic monazite phase beyond 3.8 GPa with nearly 8.6% volume discontinuity. Beyond 11 GPa, the pattern could be fitted to a similar monazite structure which is about 12.7% denser and has a much larger monoclinic beta angle. On pressure release the first monoclinic phase is recovered. The electrical resistance data show a large drop in resistance with pressure indicating substantial narrowing down of the band gap. Electronic structure calculations support these observations and suggest possible pressure induced metallization in this material. - Pressure induced structural phase transition in CeVO{sub 4} as observed by x- ray diffraction (pressure vs. volume) and possible metallization in CeVO{sub 4} through electrical resistance and first principles electronic structure calculations. - Highlights: Structural and electrical behavior of CeVO{sub 4} under pressure studied using x-ray diffraction and electrical resistance measurements and first principles calculations. Two successive structural transitions confirmed by experiment and theory: zirconmonazite Imonazite II. Band gap collapse and possible metallization is indicated by electrical resistance measurements and electronic structure calculations under pressure. Novel observation of lower bulk modulus in the high pressure phase (both by experiment and calculations) explained through structural analysis.

  17. Bacterial Production of Mixed Metal Oxide Nanoparticles - Energy...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    may be applied to cultures of a variety of metal-reducing bacteria to reduce the toxicity of dopant species to bacteria. In addition, the method provides a means by which...

  18. DEVELOPMENT OF GLASS COMPOSITIONS TO IMMOBILIZE ALKALI, ALKALINE EARTH, LANTHANIDE AND TRANSITION METAL FISSION PRODUCTS FROM NUCLEAR FUEL REPROCESSING

    SciTech Connect (OSTI)

    Marra, J.; Billings, A.

    2009-06-24

    The Advanced Fuel Cycle Initiative (AFCI) waste management strategy revolves around specific treatment of individual or groups of separated waste streams. A goal for the separations processes is to efficiently manage the waste to be dispositioned as high level radioactive waste. The Advanced Fuel Cycle Initiative (AFCI) baseline technology for immobilization of the lanthanide (Ln) and transition metal fission product (TM) wastes is vitrification into a borosilicate glass. A current interest is to evaluate the feasibility of vitrifying combined waste streams to most cost effectively immobilize the wastes resulting from aqueous fuel reprocessing. Studies showed that high waste loadings are achievable for the Ln only (Option 1) stream. Waste loadings in excess of 60 wt % (on a calcined oxide basis) were demonstrated via a lanthanide borosilicate (LaBS) glass. The resulting glasses had excellent relative durability as determined by the Product Consistency Test (PCT). For a combined Ln and TM waste stream glass (Option 2), noble metal solubility was found to limit waste loading. However, the measured PCT normalized elemental releases for this glass were at least an order of magnitude below that of Environmental Assessment (EA) glass. Current efforts to evaluate the feasibility of vitrifying combined Ln, TM, alkali (Cs is the primary radionuclide of concern) and alkaline earth (Sr is the primary radionuclide of concern) wastes (Option 3) have shown that these approaches are feasible. However, waste loading limitations with respect to heat load (Cs/Sr loading), molybdenum solubility and/or noble metal solubility will likely be realized and must be considered in determining the cost effectiveness of these approaches.

  19. DEVELOPMENT OF GLASS COMPOSITIONS TO IMMOBILIZE ALKALI, ALKALINE EARTH, LANTHANIDE AND TRANSITION METAL FISSION PRODUCTS FROM NUCLEAR FUEL REPROCESSING

    SciTech Connect (OSTI)

    Marra, James C.; Billings, Amanda Y.; Crum, Jarrod V.; Ryan, Joseph V.; Vienna, John D.

    2010-02-26

    The Advanced Fuel Cycle Initiative (AFCI) waste management strategy revolves around specific treatment of individual or groups of separated waste streams. A goal for the separations processes is to efficiently manage the waste to be dispositioned as high level radioactive waste. The Advanced Fuel Cycle Initiative (AFCI) baseline technology for immobilization of the lanthanide (Ln) and transition metal fission product (TM) wastes is vitrification into a borosilicate glass. A current interest is to evaluate the feasibility of vitrifying combined waste streams to most cost effectively immobilize the wastes resulting from aqueous fuel reprocessing. Studies showed that high waste loadings are achievable for the Ln only (Option 1) stream. Waste loadings in excess of 60 wt % (on a calcined oxide basis) were demonstrated via a lanthanide borosilicate (LaBS) glass. The resulting glasses had excellent relative durability as determined by the Product Consistency Test (PCT). For a combined Ln and TM waste stream glass (Option 2), noble metal solubility was found to limit waste loading. However, the measured PCT normalized elemental releases for this glass were at least an order of magnitude below that of Environmental Assessment (EA) glass. Current efforts to evaluate the feasibility of vitrifying combined Ln, TM, alkali (Cs is the primary radionuclide of concern) and alkaline earth (Sr is the primary radionuclide of concern) wastes (Option 3) have shown that these approaches are feasible. However, waste loading limitations with respect to heat load (Cs/Sr loading), molybdenum solubility and/or noble metal solubility will likely be realized and must be considered in determining the cost effectiveness of these approaches.

  20. Structural transition in rare earth doped zirconium oxide: A positron annihilation study

    SciTech Connect (OSTI)

    Chakraborty, Keka; Bisoi, Abhijit

    2012-11-15

    Graphical abstract: New microstructural analysis and phase transition of rare earth doped mixed oxide compounds such as: Sm{sub 2?x}Dy{sub x}Zr{sub 2}O{sub 7} (where x = 0.0 ? x ? 2.0) that are potentially useful as solid oxide fuels, ionic conductors, optoelectronic materials and most importantly as radiation resistant host for high level rad-waste disposal, structural transition in the system is reported through positron annihilation spectroscopy as there is an indication in the X-ray diffraction analysis. Highlights: ? Zirconium oxide material doped with rare earth ions. ? The method of positron annihilation spectroscopy suggests a phase transition in the system. ? The crystal structure transformation from pure pyrochlore to defect fluorite type of structure is shown by X-ray diffraction results. -- Abstract: A series of compounds with the general composition Sm{sub 2?x}Dy{sub x}Zr{sub 2}O{sub 7} (where 0 ? x ? 2.0) were synthesized by chemical route and characterized by powder X-ray diffraction (XRD) analysis. The rare earth ion namely Sm{sup +3} in the compound was gradually replaced with another smaller and heavier ion, Dy{sup +3} of the 4f series, there by resulting in orderdisorder structural transition, which has been studied by positron annihilation lifetime and Doppler broadening spectroscopy. This study reveals the subtle electronic micro environmental changes in the pyrochlore lattice (prevalent due to the oxygen vacancy in anti-site defect structure of the compound) toward its transformation to defect fluorite structure as found in Dy{sub 2}Zr{sub 2}O{sub 7}. A comparison of the changes perceived with PAS as compared to XRD analysis is critically assayed.

  1. Controlling the metal to semiconductor transition of MoS2 and WS2 in solution

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Chou, Stanley Shihyao; Yi-Kai Huang; Kim, Jaemyung; Kaehr, Bryan James; Foley, Brian M.; Lu, Ping; Conner Dykstra; Hopkins, Patrick E.; Brinker, C. Jeffrey; Jiaxing Huang; et al

    2015-01-22

    Lithiation-exfoliation produces single to few-layered MoS2 and WS2 sheets dispersible in water. However, the process transforms them from the pristine semiconducting 2H phase to a distorted metallic phase. Recovery of the semiconducting properties typically involves heating of the chemically exfoliated sheets at elevated temperatures. Therefore, it has been largely limited to sheets deposited on solid substrates. We report the dispersion of chemically exfoliated MoS2 sheets in high boiling point organic solvents enabled by surface functionalization and the controllable recovery of their semiconducting properties directly in solution. Ultimately, this process connects the scalability of chemical exfoliation with the simplicity of solutionmore » processing, enabling a facile method for tuning the metal to semiconductor transitions of MoS2 and WS2 within a liquid medium.« less

  2. First Principles Calculations of Helium Solution Energies in BCC Transition Metals

    SciTech Connect (OSTI)

    Willaime, Francois; Fu, Chu Chun

    2008-07-01

    Density functional theory calculations of the solution energies of helium in substitutional, tetrahedral and octahedral sites have been performed for all BCC transition metals: V, Nb, Ta, Cr, Mo, W and Fe. The effects of exchange correlation functional and of pseudopotential have been investigated in Fe; they are relatively small. The solution energies are found to be weakly dependent on the element for the substitutional site whereas for the interstitial sites they are much smaller in group V than in group VI and they decrease from 3d to 4d and 5d metals. As a result an inversion is observed from V, Nb and Ta - which tend to favor the interstitial site - to Mo and W, which favor the substitutional one, with an intermediate behavior for Cr and Fe. Finally, the results indicate that the tetrahedral site is always energetically more favorable than the octahedral one by 0.2 to 0.3 eV. (authors)

  3. Strain controlled metal-insulator transition in epitaxial NdNiO{sub 3} thin films

    SciTech Connect (OSTI)

    Xiang, P.-H. Zhong, N.; Duan, C.-G.; Tang, X. D.; Hu, Z. G.; Yang, P. X.; Zhu, Z. Q.; Chu, J. H.

    2013-12-28

    We have fabricated epitaxial thin films of NdNiO{sub 3} (NNO) on various single crystal substrates. The transport properties of NNO films are very sensitive to substrate-controlled epitaxial strain. As the strain varies from tensile to compressive, the Mott metal-insulator transition of NNO films shifts to low temperatures. Under a larger compressive strain, the film on LaSrAlO{sub 4} substrate exhibits a practically metallic transport characteristic. We have found that the conductivities of NNO films at low temperatures follow Mott's variable range hopping mechanism rather than thermal activation model and the epitaxial strain has a strong effect on Mott's parameters of NNO films. These findings demonstrate that the electronic transport of NNO thin films can be tuned by the epitaxial strain for next-generation perovskite-based microelectronic devices.

  4. Optical properties of monolayer transition metal dichalcogenides probed by spectroscopic ellipsometry

    SciTech Connect (OSTI)

    Liu, Hsiang-Lin Shen, Chih-Chiang; Su, Sheng-Han; Hsu, Chang-Lung; Li, Ming-Yang; Li, Lain-Jong

    2014-11-17

    Spectroscopic ellipsometry was used to characterize the complex refractive index of chemical-vapor-deposited monolayer transition metal dichalcogenides (TMDs). The extraordinary large value of the refractive index in the visible frequency range is obtained. The absorption response shows a strong correlation between the magnitude of the exciton binding energy and band gap energy. Together with the observed giant spin-orbit splitting, these findings advance the fundamental understanding of their novel electronic structures and the development of monolayer TMDs-based optoelectronic and spintronic devices.

  5. Rare-Earth Transition-Metal Intermetallics: Structure-bonding-Property Relationships

    SciTech Connect (OSTI)

    Mi-Kyung Han

    2006-05-01

    Our explorations of rare-earth, transition metal intermetallics have resulted in the synthesis and characterization, and electronic structure investigation, as well as understanding the structure-bonding-property relationships. Our work has presented the following results: (1) Understanding the relationship between compositions and properties in LaFe{sub 13-x}Si{sub x} system: A detailed structural and theoretical investigation provided the understanding of the role of a third element on stabilizing the structure and controlling the transformation of cubic NaZn{sub 13}-type structures to the tetragonal derivative, as well as the relationship between the structures and properties. (2) Synthesis of new ternary rare-earth iron silicides RE{sub 2-x}Fe{sub 4}Si{sub 14-y} and proposed superstructure: This compound offers complex structural challenges such as fractional occupancies and their ordering in superstructure. (3) Electronic structure calculation of FeSi{sub 2}: This shows that the metal-semiconductor phase transition depends on the structure. The mechanism of band gap opening is described in terms of bonding and structural distortion. This result shows that the electronic structure calculations are an essential tool for understanding the relationship between structure and chemical bonding in these compounds. (4) Synthesis of new ternary rare-earth Zinc aluminides Tb{sub 3}Zn{sub 3.6}Al{sub 7.4}: Partially ordered structure of Tb{sub 3}Zn{sub 3.6}Al{sub 7.4} compound provides new insights into the formation, composition and structure of rare-earth transition-metal intermetallics. Electronic structure calculations attribute the observed composition to optimizing metal-metal bonding in the electronegative (Zn, Al) framework, while the specific ordering is strongly influenced by specific orbital interactions. (5) Synthesis of new structure type of Zn{sub 39}(Cr{sub x}Al{sub 1-x}){sub 81}: These layered structures are similar to icosahedral Mn-Al quasicrystalline compounds. Therefore, this compound may provide new insights into the formation, composition and structure of quasicrystalline materials.

  6. Rare-earth transition-metal intermetallics: Structure-bonding-property relationships

    SciTech Connect (OSTI)

    Han, M.K.

    2006-05-06

    The explorations of rare-earth, transition metal intermetallics have resulted in the synthesis and characterization, and electronic structure investigation, as well as understanding the structure-bonding property relationships. The work has presented the following results: (1) Understanding the relationship between compositions and properties in LaFe{sub 13-x}Si{sub x} system: A detailed structural and theoretical investigation provided the understanding of the role of a third element on stabilizing the structure and controlling the transformation of cubic NaZn{sub 13}-type structures to the tetragonal derivative, as well as the relationship between the structures and properties. (2) Synthesis of new ternary rare-earth iron silicides Re{sub 2-x}Fe{sub 4}Si{sub 14-y} and proposed superstructure: This compound offers complex structural challenges such as fractional occupancies and their ordering in superstructure. (3) Electronic structure calculation of FeSi{sub 2}: This shows that the metal-semiconductor phase transition depends on the structure. The mechanism of band gap opening is described in terms of bonding and structural distortion. This result shows that the electronic structure calculations are an essential tool for understanding the relationship between structure and chemical bonding in these compounds. (4) Synthesis of new ternary rare-earth Zinc aluminides Tb{sub 3}Zn{sub 3.6}Al{sub 7.4}: Partially ordered structure of Tb{sub 3}Zn{sub 3.6}Al{sub 7.4} compound provides new insights into the formation, composition and structure of rare-earth transition-metal intermetallics. Electronic structure calculations attribute the observed composition to optimizing metal-metal bonding in the electronegative (Zn, Al) framework, while the specific ordering is strongly influenced by specific orbital interactions. (5) Synthesis of new structure type of Zn{sub 39}(Cr{sub x}Al{sub 1-x}){sub 81}: These layered structures are similar to icosahedral Mn-Al quasicrystalline compounds. Therefore, this compound may provide new insights into the formation, composition and structure of quasicrystalline materials.

  7. Metal regeneration of iron chelates in nitric oxide scrubbing

    DOE Patents [OSTI]

    Chang, Shih-Ger (El Cerrito, CA); Littlejohn, David (Oakland, CA); Shi, Yao (Berkeley, CA)

    1997-08-19

    The present invention relates to a process of using metal particles to reduce NO to NH.sub.3. More specifically, the invention concerns an improved process to regenerate iron (II) (CHELATE) by reduction of iron (II) (CHELATE) (NO) complex, which process comprises: a) contacting an aqueous solution containing iron (II) (CHELATE) (NO) with metal particles at between about 20.degree. and 90.degree. C. to reduce NO present, produce ammonia or an ammonium ion, and produce free iron (II) (CHELATE) at a pH of between about 3 and 8. The process is useful to remove NO from flue gas and reduce pollution.

  8. Metal regeneration of iron chelates in nitric oxide scrubbing

    DOE Patents [OSTI]

    Chang, S.G.; Littlejohn, D.; Shi, Y.

    1997-08-19

    The present invention relates to a process of using metal particles to reduce NO to NH{sub 3}. More specifically, the invention concerns an improved process to regenerate iron (II) (CHELATE) by reduction of iron (II) (CHELATE) (NO) complex, which process comprises: (a) contacting an aqueous solution containing iron (II) (CHELATE) (NO) with metal particles at between about 20 and 90 C to reduce NO present, produce ammonia or an ammonium ion, and produce free iron (II) (CHELATE) at a pH of between about 3 and 8. The process is useful to remove NO from flue gas and reduce pollution. 34 figs.

  9. Composite catalyst for carbon monoxide and hydrocarbon oxidation

    DOE Patents [OSTI]

    Liu, Wei (Cambridge, MA); Flytzani-Stephanopoulos, Maria (Winchester, MA)

    1996-01-01

    A method and composition for the complete oxidation of carbon monoxide and/or hydrocarbon compounds. The method involves reacting the carbon monoxide and/or hydrocarbons with an oxidizing agent in the presence of a metal oxide composite catalyst. The catalyst is prepared by combining fluorite-type oxygen ion conductors with active transition metals. The fluorite oxide, selected from the group consisting of cerium oxide, zirconium oxide, thorium oxide, hafnium oxide, and uranium oxide, and may be doped by alkaline earth and rare earth oxides. The transition metals, selected from the group consisting of molybdnum, copper, cobalt, maganese, nickel, and silver, are used as additives. The atomic ratio of transition metal to fluorite oxide is less than one.

  10. Composite catalyst for carbon monoxide and hydrocarbon oxidation

    DOE Patents [OSTI]

    Liu, W.; Flytzani-Stephanopoulos, M.

    1996-03-19

    A method and composition are disclosed for the complete oxidation of carbon monoxide and/or hydrocarbon compounds. The method involves reacting the carbon monoxide and/or hydrocarbons with an oxidizing agent in the presence of a metal oxide composite catalyst. The catalyst is prepared by combining fluorite-type oxygen ion conductors with active transition metals. The fluorite oxide, selected from the group consisting of cerium oxide, zirconium oxide, thorium oxide, hafnium oxide, and uranium oxide, and may be doped by alkaline earth and rare earth oxides. The transition metals, selected from the group consisting of molybdenum, copper, cobalt, manganese, nickel, and silver, are used as additives. The atomic ratio of transition metal to fluorite oxide is less than one.

  11. Extrinsic and intrinsic properties in metalinsulator transition of hydrothermally prepared vanadium dioxide crystals

    SciTech Connect (OSTI)

    Lee, Myeongsoon; Kim, Don

    2014-03-01

    The clear insulator (monoclinic-VO{sub 2}) to metal (rutile-VO{sub 2}) transition (IMT) was observed in electrical conductivity and differential scanning calorimeter (DSC) measurements at around 340 K, which is IMT temperature (T{sub H}), in the hydrothermally prepared VO{sub 2} crystals. The occurrence of metal to insulator transition (MIT) temperature (T{sub C}) was observed below 333 K during the first resistance measurement cycle in the most of cases. The sudden jump of the electrical resistance at IMT and MIT points was amplified several times than that of the first cycle during the repeated successive thermal cycles (heating and cooling across the IMT and MIT temperatures). T{sub C} and T{sub H} shifted to higher temperature by the repeated successive thermal cycles. This shift and the amplified jump might be related to the mechanical stress between the VO{sub 2} crystals, i.e. extrinsic properties. However, the starting point of MIT, T{sub CS} = ? 336 K, and the starting point of IMT, T{sub HS} = ? 338 K, kept almost constant during the repeated thermal cycles (< 10 times). These two temperatures may be related to the intrinsic properties of the VO{sub 2}: the phase transitions initiated at these temperatures regardless of the number of the repeated thermal cycles. The neat surface of the VO{sub 2} crystals was severely damaged and the average size of particles reduced from 110 nm to 7090 nm after extensively repeated thermal cycles (> 70 times). The damaged surface and the smaller particles, which would be originated from the mechanical stress caused by crystal volume change during the first order transition of the VO{sub 2}, would weaken the electrical conduction path (loosen grain boundaries) between the VO{sub 2} single crystals and would result in the amplified jump at the following MIT. This report may boost the study for the improved stability and lifetime of the VO{sub 2} based electronic devices. - Highlights: The sharp phase transition in cluster of VO{sub 2} crystals depends on repeated thermal cycles. Two intrinsic and two extrinsic temperatures are observed during the phase transition. The mechanical stress change and surface damage may cause the extrinsic properties in transport measurement.

  12. Mesoporous metal oxide microsphere electrode compositions and their methods of making

    DOE Patents [OSTI]

    Parans Paranthaman, Mariappan; Bi, Zhonghe; Bridges, Craig A; Brown, Gilbert M

    2014-12-16

    Compositions and methods of making are provided for treated mesoporous metal oxide microspheres electrodes. The compositions comprise (a) microspheres with an average diameter between 200 nanometers (nm) and 10 micrometers (.mu.m); (b) mesopores on the surface and interior of the microspheres, wherein the mesopores have an average diameter between 1 nm and 50 nm and the microspheres have a surface area between 50 m.sup.2/g and 500 m.sup.2/g, and wherein the composition has an electrical conductivity of at least 1.times.10.sup.-7 S/cm at 25.degree. C. and 60 MPa. The methods of making comprise forming a mesoporous metal oxide microsphere composition and treating the mesoporous metal oxide microspheres by at least one method selected from the group consisting of: (i) annealing in a reducing atmosphere, (ii) doping with an aliovalent element, and (iii) coating with a coating composition.

  13. Determination of Interfacial Adhesion Strength between Oxide Scale and Substrate for Metallic SOFC Interconnects

    SciTech Connect (OSTI)

    Sun, Xin; Liu, Wenning N.; Stephens, Elizabeth V.; Khaleel, Mohammad A.

    2008-01-21

    The interfacial adhesion strength between the oxide scale and the substrate is crucial to the reliability and durability of metallic interconnects in SOFC operating environments. It is necessary, therefore, to establish a methodology to quantify the interfacial adhesion strength between the oxide scale and the metallic interconnect substrate, and furthermore to design and optimize the interconnect material as well as the coating materials to meet the design life of an SOFC system. In this paper, we present an integrated experimental/analytical methodology for quantifying the interfacial adhesion strength between oxide scale and a ferritic stainless steel interconnect. Stair-stepping indentation tests are used in conjunction with subsequent finite element analyses to predict the interfacial strength between the oxide scale and Crofer 22 APU substrate.

  14. On the Design of High Efficiency Thermoelectric Type I Clathrates through Transition Metal Doping

    SciTech Connect (OSTI)

    Shi, Xun; Yang, Jiong; Yang, Jihui; Salvador, James R.; Bai, Shengqiang; Zhang, Weiqing; Chen, Lidong; Wong-Ng, W.; Wang, Hsin

    2010-01-01

    The lack of high efficiency thermoelectric materials hinders their deployment into wide ranging applications such as power generation from waste heat and solid state heating and cooling, which could lead to significant energy savings. Type I clathrates have recently been identified as prospective thermoelectric materials for power generation purposes due to their very low lattice thermal conductivity values. The maximum thermoelectric figure of merit of almost all type I clathrates is, however, less than 1; and occurs at, or above, 1000 K making them unfavorable especially for intermediate temperature applications. In this report, we demonstrate that transition metal doping introduces charge distortion and lattice defects into these materials which increases the ionized impurity scattering of carriers and point defect scattering of lattice phonons, respectively; leading to an enhanced power factor, reduced lattice thermal conductivity, and therefore improved thermoelectric figure of merit. Most importantly, the band gap of these materials can be tuned between 0.1 eV and 0.5 eV by adjusting the transition metal content, making it possible to design type I clathrates with excellent thermoelectric properties between 500 K and 1000 K.

  15. Oxidation/Reduction Reactions at the Metal Contact-TlBr Interface: An X-ray

    Office of Scientific and Technical Information (OSTI)

    Photoelectron Spectroscopy Study (Conference) | SciTech Connect Conference: Oxidation/Reduction Reactions at the Metal Contact-TlBr Interface: An X-ray Photoelectron Spectroscopy Study Citation Details In-Document Search Title: Oxidation/Reduction Reactions at the Metal Contact-TlBr Interface: An X-ray Photoelectron Spectroscopy Study Authors: Nelson, A J ; Swanberg, E L ; Voss, L F ; Graff, R T ; Conway, A M ; Nikolic, R J ; Payne, S A ; Kim, H ; Cirignano, L ; Shah, K Publication Date:

  16. Periodic Trends in Highly Dispersed Groups IV and V Supported Metal Oxide

    Office of Scientific and Technical Information (OSTI)

    Catalysts for Alkene Epoxidation with H[subscript 2]O[subscript 2] (Journal Article) | SciTech Connect Periodic Trends in Highly Dispersed Groups IV and V Supported Metal Oxide Catalysts for Alkene Epoxidation with H[subscript 2]O[subscript 2] Citation Details In-Document Search Title: Periodic Trends in Highly Dispersed Groups IV and V Supported Metal Oxide Catalysts for Alkene Epoxidation with H[subscript 2]O[subscript 2] Authors: Thornburg, Nicholas E. ; Thompson, Anthony B. ; Notestein,

  17. Low temperature formation of electrode having electrically conductive metal oxide surface

    DOE Patents [OSTI]

    Anders, Simone (Albany, CA); Anders, Andre (Albany, CA); Brown, Ian G. (Berkeley, CA); McLarnon, Frank R. (Orinda, CA); Kong, Fanping (Berkeley, CA)

    1998-01-01

    A low temperature process is disclosed for forming metal suboxides on substrates by cathodic arc deposition by either controlling the pressure of the oxygen present in the deposition chamber, or by controlling the density of the metal flux, or by a combination of such adjustments, to thereby control the ratio of oxide to metal in the deposited metal suboxide coating. The density of the metal flux may, in turn, be adjusted by controlling the discharge current of the arc, by adjusting the pulse length (duration of on cycle) of the arc, and by adjusting the frequency of the arc, or any combination of these parameters. In a preferred embodiment, a low temperature process is disclosed for forming an electrically conductive metal suboxide, such as, for example, an electrically conductive suboxide of titanium, on an electrode surface, such as the surface of a nickel oxide electrode, by such cathodic arc deposition and control of the deposition parameters. In the preferred embodiment, the process results in a titanium suboxide-coated nickel oxide electrode exhibiting reduced parasitic evolution of oxygen during charging of a cell made using such an electrode as the positive electrode, as well as exhibiting high oxygen overpotential, resulting in suppression of oxygen evolution at the electrode at full charge of the cell.

  18. Spinel-structured metal oxide on a substrate and method of making same by molecular beam epitaxy

    DOE Patents [OSTI]

    Chambers, Scott A.

    2006-02-21

    A method of making a spinel-structured metal oxide on a substrate by molecular beam epitaxy, comprising the step of supplying activated oxygen, a first metal atom flux, and at least one other metal atom flux to the surface of the substrate, wherein the metal atom fluxes are individually controlled at the substrate so as to grow the spinel-structured metal oxide on the substrate and the metal oxide is substantially in a thermodynamically stable state during the growth of the metal oxide. A particular embodiment of the present invention encompasses a method of making a spinel-structured binary ferrite, including Co ferrite, without the need of a post-growth anneal to obtain the desired equilibrium state.

  19. Inorganic Metal Oxide/Organic Polymer Nanocomposites And Method Thereof

    DOE Patents [OSTI]

    Gash, Alexander E.; Satcher, Joe H.; Simpson, Randy

    2004-11-16

    A synthetic method for preparation of hybrid inorganic/organic energetic nanocomposites is disclosed herein. The method employs the use of stable metal in organic salts and organic solvents as well as an organic polymer with good solubility in the solvent system to produce novel nanocomposite energetic materials. In addition, fuel metal powders (particularly those that are oxophilic) can be incorporated into composition. This material has been characterized by thermal methods, energy-filtered transmission electron microscopy (EFTEM), N.sub.2 adsoprtion/desorption methods, and Fourier-Transform (FT-IR) spectroscopy. According to these characterization methods the organic polymer phase fills the nanopores of the material, providing superb mixing of the component phases in the energetic nanocomposite.

  20. Inorganic metal oxide/organic polymer nanocomposites and method thereof

    DOE Patents [OSTI]

    Gash, Alexander E.; Satcher, Joe H.; Simpson, Randy

    2004-03-30

    A synthetic method for preparation of hybrid inorganic/organic energetic nanocomposites is disclosed herein. The method employs the use of stable metal inorganic salts and organic solvents as well as an organic polymer with good solubility in the solvent system to produce novel nanocomposite energetic materials. In addition, fuel metal powders (particularly those that are oxophillic) can be incorporated into composition. This material has been characterized by thermal methods, energy-filtered transmission electron microscopy (EFTEM), N.sub.2 adsoprtion/desorption methods, and Fourier-Transform (FT-IR) spectroscopy. According to these characterization methods the organic polymer phase fills the nanopores of the composite material, providing superb mixing of the component phases in the energetic nanocomposite.

  1. Process for making surfactant capped metal oxide nanocrystals, and products produced by the process

    DOE Patents [OSTI]

    Alivisatos, A. Paul; Rockenberger, Joerg

    2006-01-10

    Disclosed is a process for making surfactant capped nanocrystals of metal oxides which are dispersable in organic solvents. The process comprises decomposing a metal cupferron complex of the formula MXCupX, wherein M is a metal, and Cup is a N-substituted N-Nitroso hydroxylamine, in the presence of a coordinating surfactant, the reaction being conducted at a temperature ranging from about 150 to about 400.degree. C., for a period of time sufficient to complete the reaction. Also disclosed are compounds made by the process.

  2. Method of making metal oxide ceramic powders by using a combustible amino acid compound

    DOE Patents [OSTI]

    Pederson, L.R.; Chick, L.A.; Exarhos, G.J.

    1992-05-19

    This invention is directed to the formation of homogeneous, aqueous precursor mixtures of at least one substantially soluble metal salt and a substantially soluble, combustible co-reactant compound, typically an amino acid. This produces, upon evaporation, a substantially homogeneous intermediate material having a total solids level which would support combustion. The homogeneous intermediate material essentially comprises highly dispersed or solvated metal constituents and the co-reactant compound. The intermediate material is quite flammable. A metal oxide powder results on ignition of the intermediate product which combusts same to produce the product powder.

  3. Method of making metal oxide ceramic powders by using a combustible amino acid compound

    DOE Patents [OSTI]

    Pederson, Larry R. (Kennewick, WA); Chick, Lawrence A. (Richland, WA); Exarhos, Gregory J. (Richland, WA)

    1992-01-01

    This invention is directed to the formation of homogeneous, aqueous precursor mixtures of at least one substantially soluble metal salt and a substantially soluble, combustible co-reactant compound, typically an amino acid. This produces, upon evaporation, a substantially homogeneous intermediate material having a total solids level which would support combustion. The homogeneous intermediate material essentially comprises highly dispersed or solvated metal constituents and the co-reactant compound. The intermediate material is quite flammable. A metal oxide powder results on ignition of the intermediate product which combusts same to produce the product powder.

  4. Reactive sputter deposition of pyrite structure transition metal disulfide thin films: Microstructure, transport, and magnetism

    SciTech Connect (OSTI)

    Baruth, A.; Manno, M.; Narasimhan, D.; Shankar, A.; Zhang, X.; Johnson, M.; Aydil, E. S.; Leighton, C. [Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

    2012-09-01

    Transition metal disulfides crystallizing in the pyrite structure (e.g., TMS{sub 2}, with TM = Fe, Co, Ni, and Cu) are a class of materials that display a remarkably diverse array of functional properties. These properties include highly spin-polarized ferromagnetism (in Co{sub 1-x}Fe{sub x}S{sub 2}), superconductivity (in CuS{sub 2}), an antiferromagnetic Mott insulating ground state (in NiS{sub 2}), and semiconduction with close to optimal parameters for solar absorber applications (in FeS{sub 2}). Exploitation of these properties in heterostructured devices requires the development of reliable and reproducible methods for the deposition of high quality pyrite structure thin films. In this manuscript, we report on the suitability of reactive sputter deposition from metallic targets in an Ar/H{sub 2}S environment as a method to achieve exactly this. Optimization of deposition temperature, Ar/H{sub 2}S pressure ratio, and total working gas pressure, assisted by plasma optical emission spectroscopy, reveals significant windows over which deposition of single-phase, polycrystalline, low roughness pyrite films can be achieved. This is illustrated for the test cases of the ferromagnetic metal CoS{sub 2} and the diamagnetic semiconductor FeS{sub 2}, for which detailed magnetic and transport characterization are provided. The results indicate significant improvements over alternative deposition techniques such as ex situ sulfidation of metal films, opening up exciting possibilities for all-sulfide heterostructured devices. In particular, in the FeS{sub 2} case it is suggested that fine-tuning of the sputtering conditions provides a potential means to manipulate doping levels and conduction mechanisms, critical issues in solar cell applications. Parenthetically, we note that conditions for synthesis of phase-pure monosulfides and thiospinels are also identified.

  5. Non-uniform solute segregation at semi-coherent metal/oxide interfaces

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Choudhury, Samrat; Aguiar, Jeffery A.; Fluss, Michael J.; Hsiung, Luke L.; Misra, Amit; Uberuaga, Blas P.

    2015-08-26

    The properties and performance of metal/oxide nanocomposites are governed by the structure and chemistry of the metal/oxide interfaces. Here we report an integrated theoretical and experimental study examining the role of interfacial structure, particularly misfit dislocations, on solute segregation at a metal/oxide interface. We find that the local oxygen environment, which varies significantly between the misfit dislocations and the coherent terraces, dictates the segregation tendency of solutes to the interface. Depending on the nature of the solute and local oxygen content, segregation to misfit dislocations can change from attraction to repulsion, revealing the complex interplay between chemistry and structure atmore » metal/oxide interfaces. These findings indicate that the solute chemistry at misfit dislocations is controlled by the dislocation density and oxygen content. As a result, fundamental thermodynamic concepts – the Hume-Rothery rules and the Ellingham diagram – qualitatively predict the segregation behavior of solutes to such interfaces, providing design rules for novel interfacial chemistries.« less

  6. Electrochromic nickel oxide simultaneously doped with lithium and a metal dopant

    DOE Patents [OSTI]

    Gillaspie, Dane T; Weir, Douglas G

    2014-04-01

    An electrochromic device comprising a counter electrode layer comprised of lithium metal oxide which provides a high transmission in the fully intercalated state and which is capable of long-term stability, is disclosed. Methods of making an electrochromic device comprising such a counter electrode are also disclosed.

  7. Rare earth zirconium oxide buffer layers on metal substrates

    DOE Patents [OSTI]

    Williams, Robert K.; Paranthaman, Mariappan; Chirayil, Thomas G.; Lee, Dominic F.; Goyal, Amit; Feenstra, Roeland

    2001-01-01

    A laminate article comprises a substrate and a biaxially textured (RE.sub.x A.sub.(1-x)).sub.2 O.sub.2-(x/2) buffer layer over the substrate, wherein 0metal-organic decomposition. The laminate article can include a layer of YBCO over the (RE.sub.x A.sub.(1-x)).sub.2 O.sub.2-(x/2) buffer layer. A layer of CeO.sub.2 between the YBCO layer and the (RE.sub.x A.sub.(1-x)).sub.2 O.sub.2-(x/2) buffer layer can also be include. Further included can be a layer of YSZ between the CeO.sub.2 layer and the (RE.sub.x A.sub.(1-x)).sub.2 O.sub.2-(x/2) buffer layer. The substrate can be a biaxially textured metal, such as nickel. A method of forming the laminate article is also disclosed.

  8. In situ study of e-beam Al and Hf metal deposition on native oxide InP (100)

    SciTech Connect (OSTI)

    Dong, H.; KC, Santosh; Azcatl, A.; Cabrera, W.; Qin, X.; Brennan, B.; Cho, K.; Wallace, R. M.; Zhernokletov, D.

    2013-11-28

    The interfacial chemistry of thin Al (∼3 nm) and Hf (∼2 nm) metal films deposited by electron beam (e-beam) evaporation on native oxide InP (100) samples at room temperature and after annealing has been studied by in situ angle resolved X-ray photoelectron spectroscopy and low energy ion scattering spectroscopy. The In-oxides are completely scavenged forming In-In/In-(Al/Hf) bonding after Al and Hf metal deposition. The P-oxide concentration is significantly decreased, and the P-oxide chemical states have been changed to more P-rich oxides upon metal deposition. Indium diffusion through these metals before and after annealing at 250 °C has also been characterized. First principles calculation shows that In has lower surface formation energy compared with Al and Hf metals, which is consistent with the observed indium diffusion behavior.

  9. Investigation of some new hydro(solvo)thermal synthesis routes to nanostructured mixed-metal oxides

    SciTech Connect (OSTI)

    Burnett, David L.; Harunsani, Mohammad H.; Kashtiban, Reza J.; Playford, Helen Y.; Sloan, Jeremy; Hannon, Alex C.; Walton, Richard I.

    2014-06-01

    We present a study of two new solvothermal synthesis approaches to mixed-metal oxide materials and structural characterisation of the products formed. The solvothermal oxidation of metallic gallium by a diethanolamine solution of iron(II) chloride at 240 °C produces a crystalline sample of a spinel-structured material, made up of nano-scale particles typically 20 nm in dimension. XANES spectroscopy at the K-edge shows that the material contains predominantly Fe{sup 2+} in an octahedral environment, but that a small amount of Fe{sup 3+} is also present. Careful analysis using transmission electron microscopy and powder neutron diffraction shows that the sample is actually a mixture of two spinel materials: predominantly (>97%) an Fe{sup 2+} phase Ga{sub 1.8}Fe{sub 1.2}O{sub 3.9}, but with a minor impurity phase that is iron-rich. In contrast, the hydrothermal reaction of titanium bis(ammonium lactato)dihydroxide in water with increasing amounts of Sn(IV) acetate allows nanocrystalline samples of the SnO{sub 2}–TiO{sub 2} solid solution to be prepared directly, as proved by powder XRD and Raman spectroscopy. - Graphical abstract: New solvothermal synthesis approaches to spinel and rutile mixed-metal oxides are reported. - Highlights: • Solvothermal oxidation of gallium metal in organic iron(II) solution gives a novel iron gallate spinel. • Hydrothermal reaction of titanium(IV) complex and tin(IV) acetate produces the complete SnO{sub 2}–TiO{sub 2} solid solution. • Nanostructured mixed-metal oxide phases are produced directly from solution.

  10. Binding energies and spatial structures of small carrier complexes in monolayer transition-metal dichalcogenides via diffusion Monte Carlo

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Mayers, Matthew Z.; Berkelbach, Timothy C.; Hybertsen, Mark S.; Reichman, David R.

    2015-10-09

    Ground-state diffusion Monte Carlo is used to investigate the binding energies and intercarrier radial probability distributions of excitons, trions, and biexcitons in a variety of two-dimensional transition-metal dichalcogenide materials. We compare these results to approximate variational calculations, as well as to analogous Monte Carlo calculations performed with simplified carrier interaction potentials. Our results highlight the successes and failures of approximate approaches as well as the physical features that determine the stability of small carrier complexes in monolayer transition-metal dichalcogenide materials. In conclusion, we discuss points of agreement and disagreement with recent experiments.

  11. Magnetically Driven Metal-Insulator Transition in NaOsO3

    SciTech Connect (OSTI)

    Calder, Stuart A [ORNL; Christianson, Andrew D [ORNL; Lumsden, Mark D [ORNL; Lang, Jonathan [Argonne National Laboratory (ANL); Stone, Matthew B [ORNL; McMorrow, D. F. [University College, London; Garlea, Vasile O [ORNL; Kim, Jong-Woo [Argonne National Laboratory (ANL); Schlueter, J. A. [Argonne National Laboratory (ANL); Shi, Y. G. [Chinese Academy of Sciences; Yamaura, K. [National Institute for Materials Science, Tsukuba, Japan; Sun, Y. S. [MANA; Tsujimoto, Y. [Kyoto University, Japan

    2012-01-01

    The metal-insulator transition (MIT) is one of the most dramatic manifestations of electron correlations in materials. Various mechanisms producing MITs have been extensively considered, including the Mott (electron localization via Coulomb repulsion), Anderson (localization via disorder), and Peierls (local- ization via distortion of a periodic one-dimensional lattice) mechanisms. One additional route to a MIT proposed by Slater, in which long-range magnetic order in a three dimensional system drives the MIT, has received relatively little attention. Using neutron and x-ray scattering we show that the MIT in NaOsO3 is coincident with the onset of long-range commensurate three dimensional magnetic order. While candidate materials have been suggested, our experimental methodology allows the first definitive demonstration of the long predicted Slater MIT.

  12. Thermoelectric material including a multiple transition metal-doped type I clathrate crystal structure

    DOE Patents [OSTI]

    Yang, Jihui (Lakeshore, CA); Shi, Xun (Troy, MI); Bai, Shengqiang (Shanghai, CN); Zhang, Wenqing (Shanghai, CN); Chen, Lidong (Shanghai, CN); Yang, Jiong (Shanghai, CN)

    2012-01-17

    A thermoelectric material includes a multiple transition metal-doped type I clathrate crystal structure having the formula A.sub.8TM.sub.y.sub.1.sup.1TM.sub.y.sub.2.sup.2 . . . TM.sub.y.sub.n.sup.nM.sub.zX.sub.46-y.sub.1.sub.-y.sub.2.sub.- . . . -y.sub.n.sub.-z. In the formula, A is selected from the group consisting of barium, strontium, and europium; X is selected from the group consisting of silicon, germanium, and tin; M is selected from the group consisting of aluminum, gallium, and indium; TM.sup.1, TM.sup.2, and TM.sup.n are independently selected from the group consisting of 3d, 4d, and 5d transition metals; and y.sub.1, y.sub.2, y.sub.n and Z are actual compositions of TM.sup.1, TM.sup.2, TM.sup.n, and M, respectively. The actual compositions are based upon nominal compositions derived from the following equation: z=8q.sub.A-|.DELTA.q.sub.1|y.sub.1-|.DELTA.q.sub.2|y.sub.2- . . . -|.DELTA.q.sub.n|y.sub.n, wherein q.sub.A is a charge state of A, and wherein .DELTA.q.sub.1, .DELTA.q.sub.2, .DELTA.q.sub.n are, respectively, the nominal charge state of the first, second, and n-th TM.

  13. Synthesis of high {Tc} superconducting coatings and patterns by melt writing and oxidation of metallic precursor alloys

    DOE Patents [OSTI]

    Gao, W.; Vander Sande, J.B.

    1998-07-28

    A method is provided for fabrication of superconducting oxides and superconducting oxide composites and for joining superconductors to other materials. A coating of a molten alloy containing the metallic elements of the oxide is applied to a substrate surface and oxidized to form the superconducting oxide. A material can be contacted to the molten alloy which is subsequently oxidized joining the material to the resulting superconducting oxide coating. Substrates of varied composition and shape can be coated or joined by this method. 5 figs.

  14. Magnetic properties of transition metal doped AlN nanosheet: First-principle studies

    SciTech Connect (OSTI)

    Shi, Changmin; Qin, Hongwei Zhang, Yongjia; Hu, Jifan; Ju, Lin

    2014-02-07

    We carry out our first-principles calculations within density functional theory to study the 3d transition metal (TM) doped AlN nanosheets. The calculated results indicate that a stoichiometric AlN nanosheet is graphene-like structure and nonmagnetic. The TM impurities can induce magnetic moments, localized mainly on the 3d TM atoms and neighboring N atoms. Our calculated results of TM-doped nanosheet systems indicate a strong interaction between 3d orbit of TM atom and the 2p orbit of N atoms. In addition, the Mn- and Ni-doped AlN nanosheet with half-metal characters seems to be good candidates for spintronic applications. When substituting two Al atoms, the relative energies of the states between ferromagnetic and antiferromagnetic coupling are investigated sufficiently. The exchange coupling of Co- and Ni-doped AlN nanosheets exhibits a transformation with different distances of two TM atoms and that of Cr-, Mn-, and Fe-doped AlN nanosheets is not changed.

  15. Method for removing heavy metal and nitrogen oxides from flue gas, device for removing heavy metal and nitrogen oxides from flue gas

    SciTech Connect (OSTI)

    Huang, Hann-Sheng; Livengood, Charles David

    1997-12-01

    A method for the simultaneous removal of oxides and heavy metals from a fluid is provided comprising combining the fluid with compounds containing alkali and sulfur to create a mixture; spray drying the mixture to create a vapor phase and a solid phase; and isolating the vapor phase from the solid phase. A device is also provided comprising a means for spray-drying flue gas with alkali-sulfide containing liquor at a temperature sufficient to cause the flue gas to react with the compounds so as to create a gaseous fraction and a solid fraction and a means for directing the gaseous fraction to a fabric filter.

  16. Metal oxide coating of carbon supports for supercapacitor applications.

    SciTech Connect (OSTI)

    Boyle, Timothy J.; Tribby, Louis, J; Lakeman, Charles D. E.; Han, Sang M.; Lambert, Timothy N.; Fleig, Patrick F.

    2008-07-01

    The global market for wireless sensor networks in 2010 will be valued close to $10 B, or 200 M units. TPL, Inc. is a small Albuquerque based business that has positioned itself to be a leader in providing uninterruptible power supplies in this growing market with projected revenues expected to exceed $26 M in 5 years. This project focused on improving TPL, Inc.'s patent-pending EnerPak{trademark} device which converts small amounts of energy from the environment (e.g., vibrations, light or temperature differences) into electrical energy that can be used to charge small energy storage devices. A critical component of the EnerPak{trademark} is the supercapacitor that handles high power delivery for wireless communications; however, optimization and miniaturization of this critical component is required. This proposal aimed to produce prototype microsupercapacitors through the integration of novel materials and fabrication processes developed at New Mexico Technology Research Collaborative (NMTRC) member institutions. In particular, we focused on developing novel ruthenium oxide nanomaterials and placed them into carbon supports to significantly increase the energy density of the supercapacitor. These improvements were expected to reduce maintenance costs and expand the utility of the TPL, Inc.'s device, enabling New Mexico to become the leader in the growing global wireless power supply market. By dominating this niche, new customers were expected to be attracted to TPL, Inc. yielding new technical opportunities and increased job opportunities for New Mexico.

  17. Probing the transition state region in catalytic CO oxidation on Ru

    SciTech Connect (OSTI)

    Ostrom, H.; Oberg, H.; Xin, H.; LaRue, J.; Beye, M.; Dell'Angela, M.; Gladh, J.; Ng, M. L.; Sellberg, J. A.; Kaya, S.; Mercurio, G.; Nordlund, D.; Hantschmann, M.; Hieke, F.; Kuhn, D.; Schlotter, W. F.; Dakovski, G. L.; Turner, J. J.; Minitti, M. P.; Mitra, A.; Moeller, S. P.; Fohlisch, A.; Wolf, M.; Wurth, W.; Persson, M.; Norskov, J. K.; Abild-Pedersen, F.; Ogasawara, H.; Pettersson, L. G. M.; Nilsson, A.

    2015-02-12

    Femtosecond x-ray laser pulses are used to probe the CO oxidation reaction on ruthenium (Ru) initiated by an optical laser pulse. On a time scale of a few hundred femtoseconds, the optical laser pulse excites motions of CO and O on the surface, allowing the reactants to collide, and, with a transient close to a picosecond (ps), new electronic states appear in the O K-edge x-ray absorption spectrum. Density functional theory calculations indicate that these result from changes in the adsorption site and bond formation between CO and O with a distribution of OCO bond lengths close to the transition state (TS). After 1 ps, 10% of the CO populate the TS region, which is consistent with predictions based on a quantum oscillator model.

  18. Secondary cell with orthorhombic alkali metal/manganese oxide phase active cathode material

    DOE Patents [OSTI]

    Doeff, M.M.; Peng, M.Y.; Ma, Y.; Visco, S.J.; DeJonghe, L.C.

    1996-09-24

    An alkali metal manganese oxide secondary cell is disclosed which can provide a high rate of discharge, good cycling capabilities, good stability of the cathode material, high specific energy (energy per unit of weight) and high energy density (energy per unit volume). The active material in the anode is an alkali metal and the active material in the cathode comprises an orthorhombic alkali metal manganese oxide which undergoes intercalation and deintercalation without a change in phase, resulting in a substantially linear change in voltage with change in the state of charge of the cell. The active material in the cathode is an orthorhombic structure having the formula M{sub x}Z{sub y}Mn{sub (1{minus}y)}O{sub 2}, where M is an alkali metal; Z is a metal capable of substituting for manganese in the orthorhombic structure such as iron, cobalt or titanium; x ranges from about 0.2 in the fully charged state to about 0.75 in the fully discharged state, and y ranges from 0 to 60 atomic %. Preferably, the cell is constructed with a solid electrolyte, but a liquid or gelatinous electrolyte may also be used in the cell. 11 figs.

  19. Secondary cell with orthorhombic alkali metal/manganese oxide phase active cathode material

    DOE Patents [OSTI]

    Doeff, Marca M.; Peng, Marcus Y.; Ma, Yanping; Visco, Steven J.; DeJonghe, Lutgard C.

    1996-01-01

    An alkali metal manganese oxide secondary cell is disclosed which can provide a high rate of discharge, good cycling capabilities, good stability of the cathode material, high specific energy (energy per unit of weight) and high energy density (energy per unit volume). The active material in the anode is an alkali metal and the active material in the cathode comprises an orthorhombic alkali metal manganese oxide which undergoes intercalation and deintercalation without a change in phase, resulting in a substantially linear change in voltage with change in the state of charge of the cell. The active material in the cathode is an orthorhombic structure having the formula M.sub.x Z.sub.y Mn.sub.(1-y) O.sub.2, where M is an alkali metal; Z is a metal capable of substituting for manganese in the orthorhombic structure such as iron, cobalt or titanium; x ranges from about 0.2 in the fully charged state to about 0.75 in the fully discharged state, and y ranges from 0 to 60 atomic %. Preferably, the cell is constructed with a solid electrolyte, but a liquid or gelatinous electrolyte may also be used in the cell.

  20. Solid oxide fuel cell with transitioned cross-section for improved anode gas management at the open end

    DOE Patents [OSTI]

    Zafred, Paolo R. (Murrysville, PA); Draper, Robert (Pittsburgh, PA)

    2012-01-17

    A solid oxide fuel cell (400) is made having a tubular, elongated, hollow, active section (445) which has a cross-section containing an air electrode (452) a fuel electrode (454) and solid oxide electrolyte (456) between them, where the fuel cell transitions into at least one inactive section (460) with a flattened parallel sided cross-section (462, 468) each cross-section having channels (472, 474, 476) in them which smoothly communicate with each other at an interface section (458).

  1. Catalysts for the selective oxidation of hydrogen sulfide to sulfur

    DOE Patents [OSTI]

    Srinivas, Girish; Bai, Chuansheng

    2000-08-08

    This invention provides catalysts for the oxidation of hydrogen sulfide. In particular, the invention provides catalysts for the partial oxidation of hydrogen sulfide to elemental sulfur and water. The catalytically active component of the catalyst comprises a mixture of metal oxides containing titanium oxide and one or more metal oxides which can be selected from the group of metal oxides or mixtures of metal oxides of transition metals or lanthanide metals. Preferred metal oxides for combination with TiO.sub.2 in the catalysts of this invention include oxides of V, Cr, Mn, Fe, Co, Ni, Cu, Nb, Mo, Tc, Ru, Rh, Hf, Ta, W, Au, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. Catalysts which comprise a homogeneous mixture of titanium oxide and niobium (Nb) oxide are also provided. A preferred method for preparing the precursor homogenous mixture of metal hydroxides is by coprecipitation of titanium hydroxide with one or more other selected metal hydroxides. Catalysts of this invention have improved activity and/or selectivity for elemental sulfur production. Further improvements of activity and/or selectivity can be obtained by introducing relatively low amounts (up to about 5 mol %)of a promoter metal oxide (preferably of metals other than titanium and that of the selected second metal oxide) into the homogeneous metal/titanium oxide catalysts of this invention.

  2. Inert anode containing oxides of nickel iron and cobalt useful for the electrolytic production of metals

    DOE Patents [OSTI]

    Ray, Siba P. (Murrysville, PA); Liu, Xinghua (Monroeville, PA); Weirauch, Jr., Douglas A. (Murrysville, PA)

    2002-01-01

    An inert anode for the electrolytic production of metals such as aluminum is disclosed. The inert anode includes a ceramic oxide material preferably made from NiO, Fe.sub.2 O.sub.3 and CoO. The inert anode composition may comprise the following mole fractions of NiO, Fe.sub.2 O.sub.3 and CoO: 0.15 to 0.99 NiO; 0.0001 to 0.85 Fe.sub.2 O.sub.3 ; and 0.0001 to 0.45 CoO. The inert anode may optionally include other oxides and/or at least one metal phase, such as Cu, Ag, Pd, Pt, Au, Rh, Ru, Ir and/or Os. The Ni--Fe--Co--O ceramic material exhibits very low solubility in Hall cell baths used to produce aluminum.

  3. Molecular receptors in metal oxide sol-gel materials prepared via molecular imprinting

    DOE Patents [OSTI]

    Sasaki, Darryl Y. (Albuquerque, NM); Brinker, C. Jeffrey (Albuquerque, NM); Ashley, Carol S. (Albuquerque, NM); Daitch, Charles E. (Charlottesville, VA); Shea, Kenneth J. (Irvine, CA); Rush, Daniel J. (Philadelphia, PA)

    2000-01-01

    A method is provided for molecularly imprinting the surface of a sol-gel material, by forming a solution comprised of a sol-gel material, a solvent, an imprinting molecule, and a functionalizing siloxane monomer of the form Si(OR).sub.3-n X.sub.n, wherein n is an integer between zero and three and X is a functional group capable of reacting with the imprinting molecule, evaporating the solvent, and removing the imprinting molecule to form the molecularly imprinted metal oxide sol-gel material. The use of metal oxide sol-gels allows the material porosity, pore size, density, surface area, hardness, electrostatic charge, polarity, optical density, and surface hydrophobicity to be tailored and be employed as sensors and in catalytic and separations operations.

  4. Tubular solid oxide fuel cells with porous metal supports and ceramic interconnections

    DOE Patents [OSTI]

    Huang, Kevin (Export, PA); Ruka, Roswell J. (Pittsburgh, PA)

    2012-05-08

    An intermediate temperature solid oxide fuel cell structure capable of operating at from 600.degree. C. to 800.degree. C. having a very thin porous hollow elongated metallic support tube having a thickness from 0.10 mm to 1.0 mm, preferably 0.10 mm to 0.35 mm, a porosity of from 25 vol. % to 50 vol. % and a tensile strength from 700 GPa to 900 GPa, which metallic tube supports a reduced thickness air electrode having a thickness from 0.010 mm to 0.2 mm, a solid oxide electrolyte, a cermet fuel electrode, a ceramic interconnection and an electrically conductive cell to cell contact layer.

  5. Inert anode containing oxides of nickel, iron and zinc useful for the electrolytic production of metals

    DOE Patents [OSTI]

    Ray, Siba P.; Weirauch, Jr., Douglas A.; Liu, Xinghua

    2002-01-01

    An inert anode for the electrolytic production of metals such as aluminum is disclosed. The inert anode includes a ceramic oxide material preferably made from NiO, Fe.sub.2 O.sub.3 and ZnO. The inert anode composition may comprise the following mole fractions of NiO, Fe.sub.2 O.sub.3 and ZnO: 0.2 to 0.99 NiO; 0.0001 to 0.8 Fe.sub.2 O.sub.3 ; and 0.0001 to 0.3 ZnO. The inert anode may optionally include other oxides and/or at least one metal phase, such as Cu, Ag, Pd, Pt, Au, Rh, Ru, Ir and/or Os. The Ni--Fe--Co--O ceramic material exhibits very low solubility in Hall cell baths used to produce aluminum.

  6. NANOSTRUCTURED METAL OXIDES FOR ANODES OF LI-ION RECHARGEABLE BATTERIES

    SciTech Connect (OSTI)

    Au, M.

    2009-12-04

    The aligned nanorods of Co{sub 3}O{sub 4} and nanoporous hollow spheres (NHS) of SnO{sub 2} and Mn{sub 2}O{sub 3} were investigated as the anodes for Li-ion rechargeable batteries. The Co{sub 3}O{sub 4} nanorods demonstrated 1433 mAh/g reversible capacity. The NHS of SnO{sub 2} and Mn{sub 2}O{sub 3} delivered 400 mAh/g and 250 mAh/g capacities respectively in multiple galvonastatic discharge-charge cycles. It was found that high capacity of NHS of metal oxides is sustainable attributed to their unique structure that maintains material integrity during cycling. The nanostructured metal oxides exhibit great potential as the new anode materials for Li-ion rechargeable batteries with high energy density, low cost and inherent safety.

  7. Composite materials with metal oxide attached to lead chalcogenide nanocrystal quantum dots with linkers

    DOE Patents [OSTI]

    Fuke, Nobuhiro; Koposov, Alexey Y; Sykora, Milan; Hoch, Laura

    2014-12-16

    Composite materials useful for devices such as photoelectrochemical solar cells include a substrate, a metal oxide film on the substrate, nanocrystalline quantum dots (NQDs) of lead sulfide, lead selenide, and lead telluride, and linkers that attach the NQDs to the metal oxide film. Suitable linkers preserve the 1s absorption peak of the NQDs. A suitable linker has a general structure A-B-C where A is a chemical group adapted for binding to a MO.sub.x and C is a chemical group adapted for binding to a NQD and B is a divalent, rigid, or semi-rigid organic spacer moiety. Other linkers that preserve the 1s absorption peak may also be used.

  8. Temperature threshold for nanorod structuring of metal and oxide films grown by glancing angle deposition

    SciTech Connect (OSTI)

    Deniz, Derya; Lad, Robert J.

    2011-01-15

    Thin films of tin (Sn), aluminum (Al), gold (Au), ruthenium (Ru), tungsten (W), ruthenium dioxide (RuO{sub 2}), tin dioxide (SnO{sub 2}), and tungsten trioxide (WO{sub 3}) were grown by glancing angle deposition (GLAD) to determine the nanostructuring temperature threshold, {Theta}{sub T}, above which adatom surface diffusion becomes large enough such that nanorod morphology is no longer formed during growth. The threshold was found to be lower in metals compared to oxides. Films were grown using both dc and pulsed dc magnetron sputtering with continuous substrate rotation over the temperature range from 291 to 866 K. Film morphologies, structures, and compositions were characterized by high resolution scanning electron microscopy, x-ray diffraction, and x-ray photoelectron spectroscopy. Films were also grown in a conventional configuration for comparison. For elemental metals, nanorod structuring occurs for films with melting points higher than that of Al (933 K) when grown at room temperature with a rotation rate of {approx}5 rpm, corresponding to a value of {Theta}{sub T}{approx_equal}0.33{+-}0.01. For the oxide films, a value of {Theta}{sub T}{approx_equal}0.5 was found, above which GLAD nanorod structuring does not occur. The existence of a nanostructuring temperature threshold in both metal and oxide GLAD films can be attributed to greater adatom mobilities as temperature is increased resulting in nonkinetically limited film nucleation and growth processes.

  9. Oxidation Resistant, Cr Retaining, Electrically Conductive Coatings on Metallic Alloys for SOFC Interconnects

    SciTech Connect (OSTI)

    Vladimir Gorokhovsky

    2008-03-31

    This report describes significant results from an on-going, collaborative effort to enable the use of inexpensive metallic alloys as interconnects in planar solid oxide fuel cells (SOFCs) through the use of advanced coating technologies. Arcomac Surface Engineering, LLC, under the leadership of Dr. Vladimir Gorokhovsky, is investigating filtered-arc and filtered-arc plasma-assisted hybrid coating deposition technologies to promote oxidation resistance, eliminate Cr volatility, and stabilize the electrical conductivity of both standard and specialty steel alloys of interest for SOFC metallic interconnect (IC) applications. Arcomac has successfully developed technologies and processes to deposit coatings with excellent adhesion, which have demonstrated a substantial increase in high temperature oxidation resistance, stabilization of low Area Specific Resistance values and significantly decrease Cr volatility. An extensive matrix of deposition processes, coating compositions and architectures was evaluated. Technical performance of coated and uncoated sample coupons during exposures to SOFC interconnect-relevant conditions is discussed, and promising future directions are considered. Cost analyses have been prepared based on assessment of plasma processing parameters, which demonstrate the feasibility of the proposed surface engineering process for SOFC metallic IC applications.

  10. Group 4 Metalloporphyrin diolato Complexes and Catalytic Application of Metalloporphyrins and Related Transition Metal Complexes

    SciTech Connect (OSTI)

    Guodong Du

    2004-12-19

    In this work, the first examples of group 4 metalloporphyrin 1,2-diolato complexes were synthesized through a number of strategies. In general, treatment of imido metalloporphyrin complexes, (TTP)M=NR, (M = Ti, Zr, Hf), with vicinal diols led to the formation of a series of diolato complexes. Alternatively, the chelating pinacolate complexes could be prepared by metathesis of (TTP)MCl{sub 2} (M = Ti, Hf) with disodium pinacolate. These complexes were found to undergo C-C cleavage reactions to produce organic carbonyl compounds. For titanium porphyrins, treatment of a titanium(II) alkyne adduct, (TTP)Ti({eta}{sup 2}-PhC{triple_bond}CPh), with aromatic aldehydes or aryl ketones resulted in reductive coupling of the carbonyl groups to produce the corresponding diolato complexes. Aliphatic aldehydes or ketones were not reactive towards (TTP)Ti({eta}{sup 2}-PhC{triple_bond}CPh). However, these carbonyl compounds could be incorporated into a diolato complex on reaction with a reactive precursor, (TTP)Ti[O(Ph){sub 2}C(Ph){sub 2}O] to provide unsymmetrical diolato complexes via cross coupling reactions. In addition, an enediolato complex (TTP)Ti(OCPhCPhO) was obtained from the reaction of (TTP)Ti({eta}{sup 2}-PhC{triple_bond}CPh) with benzoin. Titanium porphyrin diolato complexes were found to be intermediates in the (TTP)Ti=O-catalyzed cleavage reactions of vicinal diols, in which atmospheric oxygen was the oxidant. Furthermore, (TTP)Ti=O was capable of catalyzing the oxidation of benzyl alcohol and {alpha}-hydroxy ketones to benzaldehyde and {alpha}-diketones, respectively. Other high valent metalloporphyrin complexes also can catalyze the oxidative diol cleavage and the benzyl alcohol oxidation reactions with dioxygen. A comparison of Ti(IV) and Sn(IV) porphyrin chemistry was undertaken. While chelated diolato complexes were invariably obtained for titanium porphyrins on treatment with 1,2-diols, the reaction of vicinal diols with tin porphyrins gave a number of products, including mono-, bis-alkoxo, and chelating diolato complexes, depending on the identity of diols and the stoichiometry employed. It was also found that tin porphyrin complexes promoted the oxidative cleavage of vicinal diols and the oxidation of {alpha}-ketols to {alpha}-diketones with dioxygen. In extending the chemistry of metalloporphyrins and analogous complexes, a series of chiral tetraaza macrocyclic ligands and metal complexes were designed and synthesized. Examination of iron(II) complexes showed that they were efficient catalysts for the cyclopropanation of styrene by diazo reagents. Good yields and high diastereoselectivity were obtained with modest enantioselectivity. A rationalization of the stereoselectivity was presented on the basis of structural factors in a carbene intermediate.

  11. Resistive switching in a few nanometers thick tantalum oxide film formed by a metal oxidation

    SciTech Connect (OSTI)

    Ohno, Takeo; Samukawa, Seiji

    2015-04-27

    Resistive switching in a Cu/Ta{sub 2}O{sub 5}/Pt structure that consisted of a few nanometer-thick Ta{sub 2}O{sub 5} film was demonstrated. The Ta{sub 2}O{sub 5} film with thicknesses of 25?nm was formed with a combination of Ta metal film deposition and neutral oxygen particle irradiation at room temperature. The device exhibited a bipolar resistive switching with a threshold voltage of 0.2?V and multilevel switching operation.

  12. Solubility and Surface Adsorption Characteristics of Metal Oxides to High Temperature

    SciTech Connect (OSTI)

    D.J. Wesolowski; M.L. Machesky; S.E. Ziemniak; C. Xiao; D.A. Palmer; L.M. Anovitz; P. Benezeth

    2001-05-04

    The interaction of high temperature aqueous solutions with mineral surfaces plays a key role in many aspects of fossil, geothermal and nuclear energy production. This is an area of study in which the subsurface geochemical processes that determine brine composition, porosity and permeability changes, reservoir integrity, and fluid flow rates overlap with the industrial processes associated with corrosion of metal parts and deposition of solids in pipes and on heat exchanger surfaces. The sorption of ions on mineral surfaces is also of great interest in both the subsurface and ''above ground'' regimes of power production, playing a key role in subsurface migration of contaminants (nuclear waste disposal, geothermal brine re-injection, etc.) and in plant operations (corrosion mitigation, migration of radioactive metals from reactor core to heat exchanger, etc.). In this paper, results of the solubility and surface chemistry of metal oxides relevant to both regimes are summarized.

  13. Evaluation of the thermodynamic properties of hydrated metal oxide nanoparticles by INS techniques

    SciTech Connect (OSTI)

    Spencer, Elinor; Ross, Dr. Nancy; Parker, Stewart F.; Kolesnikov, Alexander I

    2013-01-01

    In this contribution we will present a detailed methodology for the elucidation of the following aspects of the thermodynamic properties of hydrated metal oxide nanoparticles from high-resolution, low-temperature inelastic neutron scattering (INS) data: (i) the isochoric heat capacity and entropy of the hydration layers both chemi- and physisorbed to the particle surface; (ii) the magnetic contribution to the heat capacity of the nanoparticles. This will include the calculation of the vibrational density of states (VDOS) from the raw INS spectra, and the subsequent extraction of the thermodynamic data from the VDOS. This technique will be described in terms of a worked example namely, cobalt oxide (Co3O4 and CoO). To complement this evaluation of the physical properties of metal oxide nanoparticle systems, we will emphasise the importance of high-resolution, high-energy INS for the determination of the structure and dynamics of the water species, namely molecular (H2O) and dissociated water (OH, hydroxyl), confined to the oxide surfaces. For this component of the chapter we will focus on INS investigations of hydrated isostructural rutile (a-TiO2) and cassiterite (SnO2) nanoparticles. We will complete this discussion of nanoparticle analysis by including an appraisal of the INS instrumentation employed in such studies with particular focus on TOSCA [ISIS, Rutherford Appleton Laboratory (RAL), U.K.] and the newly developed spectrometer SEQUOIA [SNS, Oak Ridge National Laboratory (ORNL), U.S.A].

  14. Protective coating on positive lithium-metal-oxide electrodes for lithium batteries

    DOE Patents [OSTI]

    Johnson, Christopher S.; Thackeray, Michael M.; Kahaian, Arthur J.

    2006-05-23

    A positive electrode for a non-aqueous lithium cell comprising a LiMn2-xMxO4 spinel structure in which M is one or more metal cations with an atomic number less than 52, such that the average oxidation state of the manganese ions is equal to or greater than 3.5, and in which 0.ltoreq.x.ltoreq.0.15, having one or more lithium spine oxide LiM'2O4 or lithiated spinel oxide Li1+yM'2O4 compounds on the surface thereof in which M' are cobalt cations and in which 0.ltoreq.y.ltoreq.1.

  15. First-principles prediction of magnetic superatoms in 4d-transition-metal-doped magnesium clusters

    SciTech Connect (OSTI)

    Ge, Gui-Xian [National Laboratory of Solid State Microstructures, and Department of Physics, Nanjing University, Nanjing 210093 (China) [National Laboratory of Solid State Microstructures, and Department of Physics, Nanjing University, Nanjing 210093 (China); Key Laboratory of Ecophysics and Department of Physics, College of Science, Shihezi University, Xinjiang 832003 (China); Han, Yan; Wan, Jian-Guo, E-mail: wanjg@nju.edu.cn; Wang, Guang-Hou [National Laboratory of Solid State Microstructures, and Department of Physics, Nanjing University, Nanjing 210093 (China)] [National Laboratory of Solid State Microstructures, and Department of Physics, Nanjing University, Nanjing 210093 (China); Zhao, Ji-Jun [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Dalian University of Technology, Ministry of Education, Dalian 116024 (China)] [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Dalian University of Technology, Ministry of Education, Dalian 116024 (China)

    2013-11-07

    We theoretically predict magnetic superatoms in the 4d-transition-metal-doped Mg{sub 8} clusters using a spin-polarized density functional theory method. We demonstrate that TcMg{sub 8} is highly energetically stable in both structure and magnetic states, and identify it as a magnetic superatom with a magnetic moment as large as 5 ?{sub B}. The magnetic TcMg{sub 8} with 23 valence electrons has a configuration of 1S{sup 2}1P{sup 6}1D{sup 10} closed shell and 2S{sup 1}2D{sup 4} open shell, complying with Hund's rule similar to the single atom. We elucidate the formation mechanism of the magnetic TcMg{sub 8} superatom based on the detailed analysis of molecular orbitals, and attribute it to the large exchange interaction and moderate crystal field effect. Finally, we predict that the magnetic TcMg{sub 8} may exhibit semiconductor-like property with spin polarization characteristics.

  16. First-principles studies on graphene-supported transition metal clusters

    SciTech Connect (OSTI)

    Sahoo, Sanjubala Khanna, Shiv N.; Gruner, Markus E.; Entel, Peter

    2014-08-21

    Theoretical studies on the structure, stability, and magnetic properties of icosahedral TM{sub 13} (TM = Fe, Co, Ni) clusters, deposited on pristine (defect free) and defective graphene sheet as well as graphene flakes, have been carried out within a gradient corrected density functional framework. The defects considered in our study include a carbon vacancy for the graphene sheet and a five-membered and a seven-membered ring structures for graphene flakes (finite graphene chunks). It is observed that the presence of defect in the substrate has a profound influence on the electronic structure and magnetic properties of graphene-transition metal complexes, thereby increasing the binding strength of the TM cluster on to the graphene substrate. Among TM{sub 13} clusters, Co{sub 13} is absorbed relatively more strongly on pristine and defective graphene as compared to Fe{sub 13} and Ni{sub 13} clusters. The adsorbed clusters show reduced magnetic moment compared to the free clusters.

  17. Transition metal ion-assisted photochemical generation of alkyl halides and hydrocarbons from carboxylic acids

    SciTech Connect (OSTI)

    Carraher, Jack; Pestovsky, Oleg; Bakac, Andreja

    2012-03-14

    Near-UV photolysis of aqueous solutions of propionic acid and aqueous Fe3+ in the absence of oxygen generates a mixture of hydrocarbons (ethane, ethylene and butane), carbon dioxide, and Fe2+. The reaction becomes mildly catalytic (about five turnovers) in the presence of oxygen which converts a portion of alkyl radicals to oxidizing intermediates that reoxidize Fe2+. The photochemistry in the presence of halide ions (X? = Cl?, Br?) generates ethyl halides via halogen atom abstraction from FeXn3?n by ethyl radicals. Near-quantitative yields of C2H5X are obtained at ?0.05 M X?. Competition experiments with Co(NH3)5Br2+ provided kinetic data for the reaction of ethyl radicals with FeCl2+ (k = (4.0 0.5) 106 M?1 s?1) and with FeBr2+ (k = (3.0 0.5) 107 M?1 s?1). Photochemical decarboxylation of propionic acid in the presence of Cu2+ generates ethylene and Cu+. Longer-chain acids also yield alpha olefins as exclusive products. These reactions become catalytic under constant purge with oxygen which plays a dual role. It reoxidizes Cu+ to Cu2+, and removes gaseous olefins to prevent accumulation of Cu+(olefin) complexes and depletion of Cu2+. The results underscore the profound effect that the choice of metal ions, the medium, and reaction conditions exert on the photochemistry of carboxylic acids.

  18. Co-Al mixed metal oxides/carbon nanotubes nanocomposite prepared via a precursor route and enhanced catalytic property

    SciTech Connect (OSTI)

    Fan Guoli; Wang Hui; Xiang Xu; Li Feng

    2013-01-15

    The present work reported the synthesis of Co-Al mixed metal oxides/carbon nanotubes (CoAl-MMO/CNT) nanocomposite from Co-Al layered double hydroxide/CNTs composite precursor (CoAl-LDH/CNT). The materials were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), low temperature nitrogen adsorption-desorption experiments, thermogravimetric and differential thermal analyses (TG-DTA), Raman spectra and X-ray photoelectron spectroscopy (XPS). The results revealed that in CoAl-MMO/CNT nanocomposite, the nanoparticles of cobalt oxide (CoO) and Co-containing spinel-type complex metal oxides could be well-dispersed on the surface of CNTs, thus forming the heterostructure of CoAl-MMO and CNTs. Furthermore, as-synthesized CoAl-MMO/CNT nanocomposite was utilized as additives for catalytic thermal decomposition of ammonium perchlorate (AP). Compared to those for pure AP and CoAl-MMO, the peak temperature of AP decomposition for CoAl-MMO/CNT was significantly decreased, which is attributed to the novel heterostructure and synergistic effect of multi-component metal oxides of nanocomposite. - Graphical abstract: Hybrid Co-Al mixed metal oxides/carbon nanotubes nanocomposite showed the enhanced catalytic activity in the thermal decomposition of ammonium perchlorate, as compared to carbon nanotubes and pure Co-Al mixed metal oxides. Highlights: Black-Right-Pointing-Pointer Co-Al mixed metal oxides/carbon nanotubes nanocomposite was synthesized. Black-Right-Pointing-Pointer Co-Al mixed metal oxides consisted of cobalt oxide and Co-containing spinels. Black-Right-Pointing-Pointer Nanocomposite exhibited excellent catalytic activity for the decomposition of AP. Black-Right-Pointing-Pointer The superior catalytic property is related to novel heterostructure and composition.

  19. WASP-36b: A NEW TRANSITING PLANET AROUND A METAL-POOR G-DWARF, AND AN INVESTIGATION INTO ANALYSES BASED ON A SINGLE TRANSIT LIGHT CURVE

    SciTech Connect (OSTI)

    Smith, A. M. S.; Anderson, D. R.; Hellier, C.; Maxted, P. F. L.; Smalley, B.; Southworth, J.; Collier Cameron, A.; Gillon, M.; Jehin, E.; Lendl, M.; Queloz, D.; Triaud, A. H. M. J.; Pepe, F.; Segransan, D.; Udry, S.; West, R. G.; Barros, S. C. C.; Pollacco, D.; Street, R. A.

    2012-04-15

    We report the discovery, from WASP and CORALIE, of a transiting exoplanet in a 1.54 day orbit. The host star, WASP-36, is a magnitude V = 12.7, metal-poor G2 dwarf (T{sub eff} = 5959 {+-} 134 K), with [Fe/H] =-0.26 {+-} 0.10. We determine the planet to have mass and radius, respectively, 2.30 {+-} 0.07 and 1.28 {+-} 0.03 times that of Jupiter. We have eight partial or complete transit light curves, from four different observatories, which allow us to investigate the potential effects on the fitted system parameters of using only a single light curve. We find that the solutions obtained by analyzing each of these light curves independently are consistent with our global fit to all the data, despite the apparent presence of correlated noise in at least two of the light curves.

  20. Small cell experiments for electrolytic reduction of uranium oxides to uranium metal using fluoride salts

    SciTech Connect (OSTI)

    Haas, P.A.; Adcock, P.W.; Coroneos, A.C.; Hendrix, D.E. )

    1994-08-01

    Electrolytic reduction of uranium oxide was proposed for the preparation of uranium metal feed for the atomic vapor laser isotope separation (AVLIS) process. A laboratory cell of 25-cm ID was operated to obtain additional information in areas important to design and operation of a pilot plant cell. Reproducible test results and useful operating and control procedures were demonstrated. About 20 kg of uranium metal of acceptable purity were prepared. A good supply of dissolved UO[sub 2] feed at the anode is the most important controlling requirement for efficient cell operation. A large fraction of the cell current is nonproductive in that it does not produce a metal product nor consume carbon anodes. All useful test conditions gave some reduction of UF[sub 4] to produce CF[sub 4] in addition to the reduction of UO[sub 2], but the fraction of metal from the reduction of UF[sub 4] can be decreased by increasing the concentration of dissolved UO[sub 2]. Operation of large continuous cells would probably be limited to current efficiencies of less than 60 pct, and more than 20 pct of the metal would result from the reduction of UF[sub 4].

  1. Transition Metal Catalyzed Hydroarylation of Multiple Bonds: Exploration of Second Generation Ruthenium Catalysts and Extension to Copper Systems

    SciTech Connect (OSTI)

    T. Brent Gunnoe

    2011-02-17

    Catalysts provide foundational technology for the development of new materials and can enhance the efficiency of routes to known materials. New catalyst technologies offer the possibility of reducing energy and raw material consumption as well as enabling chemical processes with a lower environmental impact. The rising demand and expense of fossil resources has strained national and global economies and has increased the importance of accessing more efficient catalytic processes for the conversion of hydrocarbons to useful products. The goals of the research are to develop and understand single-site homogeneous catalysts for the conversion of readily available hydrocarbons into useful materials. A detailed understanding of these catalytic reactions could lead to the development of catalysts with improved activity, longevity and selectivity. Such transformations could reduce the environmental impact of hydrocarbon functionalization, conserve energy and valuable fossil resources and provide new technologies for the production of liquid fuels. This project is a collaborative effort that incorporates both experimental and computational studies to understand the details of transition metal catalyzed C-H activation and C-C bond forming reactions with olefins. Accomplishments of the current funding period include: (1) We have completed and published studies of C-H activation and catalytic olefin hydroarylation by TpRu{l_brace}P(pyr){sub 3}{r_brace}(NCMe)R (pyr = N-pyrrolyl) complexes. While these systems efficiently initiate stoichiometric benzene C-H activation, catalytic olefin hydroarylation is hindered by inhibition of olefin coordination, which is a result of the steric bulk of the P(pyr){sub 3} ligand. (2) We have extended our studies of catalytic olefin hydroarylation by TpRu(L)(NCMe)Ph systems to L = P(OCH{sub 2}){sub 3}CEt. Thus, we have now completed detailed mechanistic studies of four systems with L = CO, PMe{sub 3}, P(pyr){sub 3} and P(OCH{sub 2}){sub 3}CEt, which has provided a comprehensive understanding of the impact of steric and electronic parameters of 'L' on the catalytic hydroarylation of olefins. (3) We have completed and published a detailed mechanistic study of stoichiometric aromatic C-H activation by TpRu(L)(NCMe)Ph (L = CO or PMe{sub 3}). These efforts have probed the impact of functionality para to the site of C-H activation for benzene substrates and have allowed us to develop a detailed model of the transition state for the C-H activation process. These results have led us to conclude that the C-H bond cleavage occurs by a {sigma}-bond metathesis process in which the C-H transfer is best viewed as an intramolecular proton transfer. (4) We have completed studies of Ru complexes possessing the N-heterocyclic carbene IMes (IMes = 1,3-bis-(2,4,6-trimethylphenyl)imidazol-2-ylidene). One of these systems is a unique four-coordinate Ru(II) complex that catalyzes the oxidative hydrophenylation of ethylene (in low yields) to produce styrene and ethane (utilizing ethylene as the hydrogen acceptor) as well as the hydrogenation of olefins, aldehydes and ketones. These results provide a map for the preparation of catalysts that are selective for oxidative olefin hydroarylation. (5) The ability of TpRu(PMe{sub 3})(NCMe)R systems to activate sp{sup 3} C-H bonds has been demonstrated including extension to subsequent C-C bond forming steps. These results open the door to the development of catalysts for the functionalization of more inert C-H bonds. (6) We have discovered that Pt(II) complexes supported by simple nitrogen-based ligands serve as catalysts for the hydroarylation of olefins. Given the extensive studies of Pt-based catalytic C-H activation, we believe these results will provide an entry point into an array of possible catalysts for hydrocarbon functionalization.

  2. Increased photocatalytic activity of TiO2 mesoporous microspheres from codoping with transition metals and nitrogen

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Mathis, John E.; Lieffers, Justin J.; Mitra, Chandrima; Reboredo, Fernando A.; Bi, Z.; Bridges, Craig A.; Kidder, Michelle K.; Paranthaman, Mariappan Parans

    2015-11-06

    The composition of anatase TiO2 was modified by codoping using combinations of a transition metal and nitrogen in order to increase its photocatalytic activity and extend it performance in the visible region of the electromagnetic spectrum. The transition metals (Mn, Co, Ni, Cu) were added during the hydrothermal preparation of mesoporous TiO2 particles, and the nitrogen was introduced by post-annealing in flowing ammonia gas at high temperature. The samples were analyzed by SEM, XRD, BET, inductively-coupled plasma spectroscopy, and diffuse reflectance UV-vis spectroscopy. The photocatalytic activity was assessed by observing the change in methylene blue concentrations under both UV-vis andmore » visible-only light irradiation. As a result, the photocatalytic activity of the (Mn,N), (Co,N), (Cu,N), and Ni,N) codoped TiO2 was significantly enhanced relative to (N) TiO2.« less

  3. Elastic-plastic and phase transition of zinc oxide single crystal under shock compression

    SciTech Connect (OSTI)

    Liu, Xun; Mashimo, Tsutomu Li, Wei; Zhou, Xianming; Sekine, Toshimori

    2015-03-07

    The Hugoniot data for zinc oxide (ZnO) single crystals were measured up to 80 GPa along both the 〈112{sup ¯}0〉 (a-axis) and 〈0001〉 (c-axis) directions using a velocity interferometer system for any reflector and inclined-mirror method combined with a powder gun and two-stage light gas gun. The Hugoniot-elastic limits of ZnO were determined to be 10.5 and 11.5 GPa along the a- and c-axes, respectively. The wurtzite (B4) to rocksalt (B1) phase transition pressures along the a- and c-axes are 12.3 and 14.4 GPa, respectively. Shock velocity (U{sub s}) versus particle velocity (U{sub p}) relation of the final phase is given by the following relationship: U{sub s} (km/s) = 2.76 + 1.51U{sub p} (km/s). Based on the Debye-Grüneisen model and Birch-Murnaghan equation of state (EOS), we discuss the EOS of the B1 phase ZnO. The bulk modulus (K{sub 0}) and its pressure derivative (K{sub 0}′) are estimated to be K{sub 0} = 174 GPa and K{sub 0}′ = 3.9, respectively.

  4. Selective Catalytic Oxidation (SCO) of NH3 to N2 for Hot Exhaust...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Oxidation (SCO) of NH3 to N2 for Hot Exhaust Treatment Selective Catalytic Oxidation (SCO) of NH3 to N2 for Hot Exhaust Treatment Investigation of a series of transition metal...

  5. High Temperature Strength of YSZ Joints Brazed with Palladium Silver Copper Oxide Filler Metals

    SciTech Connect (OSTI)

    Darsell, Jens T.; Weil, K. Scott

    2010-06-09

    The Ag-CuOx system is being investigated as potential filler metals for use in air brazing high-temperature electrochemical devices such as solid oxide fuel cells and gas concentrators. The current study examines the effects of palladium addition on the high temperature joint strength of specimens prepared from yttria stabilized zirconia (YSZ) bars brazed with the binary Ag-CuOx, and 15Pd-Ag-CuO. It was found that while the binary Ag-CuOx system exhibits stronger room temperature strength than the 15Pd system the strength is reduced to values equivalent of the 15Pd system at 800C. The 15Pd system exhibits a lower ambient temperature strength that is retained at 800C. In both systems the failure mechanism at high temperature appears to be peeling of the noble metal component from the oxide phases and tearing through the noble metal phase whereas sufficient adhesion is retained at lower temperatures to cause fracture of the YSZ substrate.

  6. Manganese Doping of Magnetic Iron Oxide Nanoparticles: Tailoring Surface Reactivity for a Regenerable Heavy Metal Sorbent

    SciTech Connect (OSTI)

    Warner, Cynthia L.; Chouyyok, Wilaiwan; Mackie, Katherine E.; Neiner, Doinita; Saraf, Laxmikant; Droubay, Timothy C.; Warner, Marvin G.; Addleman, Raymond S.

    2012-02-28

    A method for tuning the analyte affinity of magnetic, inorganic nanostructured sorbents for heavy metal contaminants is described. The manganese-doped iron oxide nanoparticle sorbents have a remarkably high affinity compared to the precursor material. Sorbent affinity can be tuned toward an analyte of interest simply by adjustment of the dopant quantity. The results show that following the Mn doping process there is a large increase in affinity and capacity for heavy metals (i.e., Co, Ni, Zn, As, Ag, Cd, Hg, and Tl). Capacity measurements were carried out for the removal of cadmium from river water and showed significantly higher loading than the relevant commercial sorbents tested for comparison. The reduction in Cd concentration from 100 ppb spiked river water to 1 ppb (less than the EPA drinking water limit of 5 ppb for Cd) was achieved following treatment with the Mn-doped iron oxide nanoparticles. The Mn-doped iron oxide nanoparticles were able to load 1 ppm of Cd followed by complete stripping and recovery of the Cd with a mild acid wash. The Cd loading and stripping is shown to be consistent through multiple cycles with no loss of sorbent performance.

  7. The synthesis and structure of new transition metal lithium calcium nitride compounds

    SciTech Connect (OSTI)

    Hunting, Janet L.; Szymanski, Marta M.; Kowalsick, Amanda L.; Downie, Craig M.; DiSalvo, Francis J.

    2013-01-15

    Three new nitrides, Li{sub 3}Ca{sub 2}V{sub 0.79}Nb{sub 0.21}N{sub 4}, Li{sub 2}Ca{sub 2.67}Nb{sub 0.33}N{sub 3} and Li{sub 12}Ca{sub 9}W{sub 5}N{sub 20}, were synthesized in sealed niobium tubes using lithium nitride as a flux at temperatures ranging from 800 Degree-Sign C to 1050 Degree-Sign C. In all of these compounds, the transition metals are coordinated tetrahedrally by nitrogen; these tetrahedra are isolated from each other. Bullet Li{sub 3}Ca{sub 2}V{sub 0.79}Nb{sub 0.21}N{sub 4}, space group P2{sub 1}/m (no. 11), cell parameters a=5.7669(8) A, b=6.9123(9) A, c=6.0116(12) A, {beta}=90.727(9) Degree-Sign , Z=2, has a shared vanadium/niobium tetrahedral position which shares vertices with the tetrahedrally-coordinated lithium position. Bullet Li{sub 2}Ca{sub 2.67}Nb{sub 0.33}N{sub 3}, space group Req /o(3, Macron )m (no. 166), cell parameters a=3.6311(2) A, c=29.459(3) A, Z=3, contains a disordered tetrahedral calcium/niobium position, an octahedral calcium position and a triangularly coordinated lithium position. Bullet Li{sub 12}Ca{sub 9}W{sub 5}N{sub 20}, space group C2/c (no. 15), cell parameters a=27.7347(19) A, b=8.6652(6) A, c=10.7685(7) A, {beta}=110.314(2) Degree-Sign , Z=4, contains three crystallographically different tungsten positions as well as one disordered lithium position. - Graphical abstract: Crystal structure of Li{sub 3}Ca{sub 2}V{sub 0.79}Nb{sub 0.21}N{sub 4} depicting the chains of edge-sharing LiN{sub 4} (light hatching) and (V/Nb)N{sub 4} (dark hatching) tetrahedra viewed approximately along the [100] direction. Calcium atoms are shown as open circles and nitrogen atoms are colored black. Highlights: Black-Right-Pointing-Pointer Three new lithium calcium nitrides are synthesized. Black-Right-Pointing-Pointer Lithium nitride flux used in synthesis. Black-Right-Pointing-Pointer Structures contain isolated tetrahedrally coordinated transition metals. Black-Right-Pointing-Pointer Li{sub 12}Ca{sub 9}W{sub 5}N{sub 20} contains three crystallographically different W positions.

  8. Variation of the shape and morphological properties of silica and metal oxide powders by electro homogeneous precipitation

    DOE Patents [OSTI]

    Harris, Michael T. (Knoxville, TN); Basaran, Osman A. (Oak Ridge, TN); Sisson, Warren G. (Oak Ridge, TN); Brunson, Ronald R. (Lenoir City, TN)

    1997-01-01

    The present invention provides a method for preparing irreversible linear aggregates (fibrils) of metal oxide powders by utilizing static or pulsed DC electrical fields across a relatively non-conducting liquid solvent in which organometal compounds or silicon alkoxides have been dissolved. The electric field is applied to the relatively non-conducting solution throughout the particle formation and growth process promoting the formation of either linear aggregates (fibrils) or spherical shaped particles as desired. Thus the present invention provides a physical method for altering the size, shape and porosity of precursor hydrous metal oxide or hydrous silicon oxide powders for the development of advanced ceramics with improved strength and insulating capacity.

  9. Low temperature photochemical vapor deposition of alloy and mixed metal oxide films

    DOE Patents [OSTI]

    Liu, D.K.

    1992-12-15

    Method and apparatus are described for formation of an alloy thin film, or a mixed metal oxide thin film, on a substrate at relatively low temperatures. Precursor vapor(s) containing the desired thin film constituents is positioned adjacent to the substrate and irradiated by light having wavelengths in a selected wavelength range, to dissociate the gas(es) and provide atoms or molecules containing only the desired constituents. These gases then deposit at relatively low temperatures as a thin film on the substrate. The precursor vapor(s) is formed by vaporization of one or more precursor materials, where the vaporization temperature(s) is selected to control the ratio of concentration of metals present in the precursor vapor(s) and/or the total precursor vapor pressure. 7 figs.

  10. Low temperature photochemical vapor deposition of alloy and mixed metal oxide films

    DOE Patents [OSTI]

    Liu, David K.

    1992-01-01

    Method and apparatus for formation of an alloy thin film, or a mixed metal oxide thin film, on a substrate at relatively low temperatures. Precursor vapor(s) containing the desired thin film constituents is positioned adjacent to the substrate and irradiated by light having wavelengths in a selected wavelength range, to dissociate the gas(es) and provide atoms or molecules containing only the desired constituents. These gases then deposit at relatively low temperatures as a thin film on the substrate. The precursor vapor(s) is formed by vaporization of one or more precursor materials, where the vaporization temperature(s) is selected to control the ratio of concentration of metals present in the precursor vapor(s) and/or the total precursor vapor pressure.

  11. Irradiation of Metallic and Oxide Fuels for Actinide Transmutation in the ATR

    SciTech Connect (OSTI)

    MacLean, Heather J.; Hayes, Steven L.

    2007-07-01

    Metallic fuels containing minor actinides and rare earth additions have been fabricated and are prepared for irradiation in the ATR, scheduled to begin during the summer of 2007. Oxide fuels containing minor actinides are being fabricated and will be ready for irradiation in ATR, scheduled to begin during the summer of 2008. Fabrication and irradiation of these fuels will provide detailed studies of actinide transmutation in support of the Global Nuclear Energy Partnership. These fuel irradiations include new fuel compositions that have never before been tested. Results from these tests will provide fundamental data on fuel irradiation performance and will advance the state of knowledge for transmutation fuels. (authors)

  12. Rapid thermal cycling of metal-supported solid oxide fuel cellmembranes

    SciTech Connect (OSTI)

    Matus, Yuriy B.; De Jonghe, Lutgard C.; Jacobson, Craig P.; Visco, Steven J.

    2004-01-02

    Solid oxide fuel cell (SOFC) membranes were developed in which zirconia-based electrolyte thin films were supported by a composite metal/ceramic electrode, and were subjected to rapid thermal cycling between 200 and 800 C. The effects of this cycling on membrane performance were evaluated. The membranes, not yet optimized for performance, showed a peak power density of 350mW/cm2at 900 C in laboratory-sized SOFCs that was not affected by the thermal cycling. This resistance to cycling degradation is attributed to the close matching of thermal expansion coefficient of the cermet support electrode with that of the zirconia electrolyte.

  13. Transitions between strongly correlated and random steady-states for catalytic CO-oxidation on surfaces at high-pressure

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Liu, Da -Jiang; Evans, James W.

    2015-04-02

    We explore simple lattice-gas reaction models for CO-oxidation on 1D and 2D periodic arrays of surface adsorption sites. The models are motivated by studies of CO-oxidation on RuO2(110) at high-pressures. Although adspecies interactions are neglected, the effective absence of adspecies diffusion results in kinetically-induced spatial correlations. A transition occurs from a random mainly CO-populated steady-state at high CO-partial pressure pCO, to a strongly-correlated near-O-covered steady-state for low pCO as noted. In addition, we identify a second transition to a random near-O-covered steady-state at very low pCO.

  14. Two Keggin-type heteropolytungstates with transition metal as a central atom: Crystal structure and magnetic study with 2D-IR correlation spectroscopy

    SciTech Connect (OSTI)

    Chai, Feng [Department of Chemistry, Fuzhou University, Fuzhou 350108 (China); Chen, YiPing, E-mail: ypchen007@sina.com [Department of Chemistry, Fuzhou University, Fuzhou 350108 (China); State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China); You, ZhuChai; Xia, ZeMin; Ge, SuZhi; Sun, YanQiong; Huang, BiHua [Department of Chemistry, Fuzhou University, Fuzhou 350108 (China)

    2013-06-01

    Two Keggin-type heteropolytungstates, [Co(phen)?]?[CoW??O??]9H?O 1 (phen=1,10-phenanthroline) and [Fe(phen)?]?[FeW??O??]H?OH?O 2, have been synthesized via the hydrothermal technique and characterized by single crystal X-ray diffraction analyses, IR, XPS, TG analysis, UVDRS, XRD, thermal-dependent and magnetic-dependent 2D-COS IR (two-dimensional infrared correlation spectroscopy). Crystal structure analysis reveals that the polyanions in compound 1 are linked into 3D supramolecule through hydrogen bonding interactions between lattice water molecules and terminal oxygen atoms of polyanion units, and [Co(phen)?]? cations distributed in the polyanion framework with many hydrogen bonding interactions. The XPS spectra indicate that all the Co atoms in 1 are +2 oxidation state, the Fe atoms in 2 existing with +2 and +3 mixed oxidation states. - Graphical abstract: The magnetic-dependent synchronous 2D correlation IR spectra of 1 (a), 2 (b) over 050 mT in the range of 6001000 cm?, the obvious response indicate two Keggin polyanions skeleton susceptible to applied magnetic field. Highlights: Two Keggin-type heteropolytungstates with transition metal as a central atom has been obtained. Compound 1 forms into 3D supramolecular architecture through hydrogen bonding between water molecules and polyanions. Magnetic-dependent 2D-IR correlation spectroscopy was introduced to discuss the magnetism of polyoxometalate.

  15. Effects of heavy metals on biomarkers for oxidative stress in Griffon vulture (Gyps fulvus)

    SciTech Connect (OSTI)

    Espn, Silvia; Martnez-Lpez, Emma; Jimnez, Pedro; Mara-Mojica, Pedro; Garca-Fernndez, Antonio J.

    2014-02-01

    Metals are involved in the formation of reactive oxygen species (ROS) which may result in metal-related oxidative stress that can lead to oxidative damage to lipids, DNA and proteins. It is necessary to understand the mechanisms of metal toxicity in wild birds, and the concentrations that cause effects on oxidative stress biomarkers. The aim of this study is to assess the concentrations of lead (Pb), cadmium (Cd), mercury (Hg), copper (Cu) and zinc (Zn) with regards to oxidative stress in blood samples of 66 Griffon vultures (Gyps fulvus) from two areas of the Autonomous Community of Valencia (East of Spain). The two study areas (Alcoy n=36 and Cinctorres n=30) were selected as random locations of interest that had not yet been studied, and are feeding stations where supplementary food, mainly of pork origin, is provided for vultures. Given that the two study areas are not considered polluted sites, we expected to find low metal concentrations. However, there are no known threshold concentrations at which metals can affect antioxidant systems, and low metal levels may have an effect on antioxidant biomolecules. In this study, since sampling was done at the beginning of the hunting season, the low Pb levels found in most Griffon vultures from Alcoy and Cinctorres (median=12.37 and 16.26 ?g/dl, respectively) are suggestive of background levels usually found in vultures that feed on pork carcasses all year round. The ingestion of game meat with bullet fragments in carcasses or with Pb shots embedded in the flesh could be the cause of the high blood Pb concentrations found in three vultures from Cinctorres (83, 290 and 362 ?g/dl). Griffon vultures feeding in Cinctorres had enhanced CAT and GST activities and tGSH concentrations, which may be interpreted as protective response against the higher TBARS levels. This study provides threshold concentrations at which metals affect antioxidant system derived from 66 samples of Griffon vulture. Blood Cd concentrations greater than 0.05 ?g/dl produced an induction of 33% in GPx and of 44% in CAT activity in erythrocytes of vultures from Alcoy. Hg concentrations in blood higher than 3 ?g/dl produced an induction of 10% in SOD activity. Concentrations of Pb above 15 g/dl in blood produced an inhibition of 12.5% in GPx and 11.3% in CAT activity, and a TBARS induction of 10.7% in erythrocytes of Griffon vultures. - Highlights: Except for 3 Griffon vultures, lead levels could be considered background levels. Three vultures may be exposed to meat with bullet fragments (blood Pb=83362 ?g/dl). Blood Cd levels?0.05 ?g/dl caused an induction of GPx and CAT activity (33% and 44%). Blood Hg levels?3 ?g/dl caused an induction of 10% in SOD activity. Blood Pb?15 g/dl caused an inhibition of GPx and CAT activity and a TBARS induction.

  16. Impact of Iron-Reducing Bacteria on Metals and Radionuclides Adsorbed to Humic-Coated Iron(III) Oxides

    SciTech Connect (OSTI)

    Burgos, W. D.

    2005-02-01

    This is the final report for Grant No. DEFGO2-98ER62691 submitted to the DOE NABR Program. This research has focused on (1) the role of natural organic matter (NOM), quinines, and complexants in enhancing the biological reduction of solid-phase crystalline ferric oxides, (2) the effect of heavy metals (specifically zinc) and NOM on ferric oxide bioreduction, (3) the sorption of Me(II) [Cu(II), Fe(II), Mn(II) and Zn(II)] to ferric oxides and subsequent Me(II)-promoted phase transformations of the ferric oxides, and (4) the development of reaction-based biogeochemical models to numerically simulate our experimental results.

  17. Method and apparatus for preparation of spherical metal carbonates and lithium metal oxides for lithium rechargeable batteries

    DOE Patents [OSTI]

    Kang, Sun-Ho; Amine, Khalil

    2008-10-14

    A number of materials with the composition Li.sub.1+xNi.sub..alpha.Mn.sub..beta.Co.sub..gamma.M'.sub..delta.O.sub.2-- zF.sub.z (M'=Mg,Zn,Al,Ga,B,Zr,Ti) for use with rechargeable batteries, wherein x is between about 0 and 0.3, .alpha. is between about 0.2 and 0.6, .beta. is between about 0.2 and 0.6, .gamma. is between about 0 and 0.3, .delta. is between about 0 and 0.15, and z is between about 0 and 0.2. Adding the above metal and fluorine dopants affects capacity, impedance, and stability of the layered oxide structure during electrochemical cycling. Another aspect of the invention includes materials with the composition Li.sub.1+xNi.sub..alpha.Co.sub..beta.Mn.sub..gamma.M'.sub..delta.O.sub.yF- .sub.z (M'=Mg,Zn,Al,Ga,B,Zr,Ti), where the x is between 0 and 0.2, the .alpha. between 0 and 1, the .beta. between 0 and 1, the .gamma. between 0 and 2, the .delta. between about 0 and about 0.2, the y is between 2 and 4, and the z is between 0 and 0.5.

  18. Effect of pre-oxidation and environmental aging on the seal strength of a novel high-temperature solid oxide fuel cell (SOFC) sealing glass with metallic interconnect

    SciTech Connect (OSTI)

    Chou, Y. S.; Stevenson, Jeffry W.; Singh, Prabhakar

    2008-09-15

    A novel high-temperature alkaline-earth silicate sealing glass was developed for solid oxide fuel cell (SOFC) applications. The glass was used to join two ferritic stainless steel coupons for strength evaluation. The steel coupons were pre-oxidized at elevated temperatures to promote thick oxide layers to simulate long-term exposure conditions. In addition, seals to as-received metal coupons were also tested after aging in oxidizing or reducing environments to simulate the actual SOFC environment. Room temperature tensile testing showed strength degradation when using pre-oxidized coupons, and more extensive degradation after aging in air. Fracture surface and microstructural analysis confirmed that the cause of degradation was formation of SrCrO4 at the outer sealing edges exposed to air.

  19. Selective Catalytic Oxidation (SCO) of NH3 to N2 for Hot Exhaust Treatment

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    | Department of Energy Oxidation (SCO) of NH3 to N2 for Hot Exhaust Treatment Selective Catalytic Oxidation (SCO) of NH3 to N2 for Hot Exhaust Treatment Investigation of a series of transition metal oxides and precious metal based catalysts for ammonia selective oxidation at low temperatures PDF icon deer12_thrun.pdf More Documents & Publications Deactivation Mechanisms of Base Metal/Zeolite Urea Selective Catalytic Reduction Materials, and Development of Zeolite-Based Hydrocarbon

  20. Disposition of Uranium -233 (sup 233U) in Plutonium Metal and Oxide at the Rocky Flats Environmental Technology Site

    SciTech Connect (OSTI)

    Freiboth, Cameron J.; Gibbs, Frank E.

    2000-03-01

    This report documents the position that the concentration of Uranium-233 ({sup 233}U) in plutonium metal and oxide currently stored at the DOE Rocky Flats Environmental Technology Site (RFETS) is well below the maximum permissible stabilization, packaging, shipping and storage limits. The {sup 233}U stabilization, packaging and storage limit is 0.5 weight percent (wt%), which is also the shipping limit maximum. These two plutonium products (metal and oxide) are scheduled for processing through the Building 371 Plutonium Stabilization and Packaging System (PuSPS). This justification is supported by written technical reports, personnel interviews, and nuclear material inventories, as compiled in the ''History of Uranium-233 ({sup 233}U) Processing at the Rocky Flats Plant In Support of the RFETS Acceptable Knowledge Program'' RS-090-056, April 1, 1999. Relevant data from this report is summarized for application to the PuSPS metal and oxide processing campaigns.

  1. X-Ray Absorption Studies of Vanadium-Containing Metal Oxide Nanocrystals

    SciTech Connect (OSTI)

    Hohn, Keith, L.

    2006-01-09

    Metal oxide nanocrystals offer significant potential for use as catalysts or catalyst supports due to their high surface areas and unique chemical properties that result from the high number of exposed corners and edges. However, little is known about the catalytic activity of these materials, especially as oxidation catalysts. This research focused on the preparation, characterization and use of vanadium-containing nanocrystals as selective oxidation catalysts. Three vanadium-containing nanocrystals were prepared using a modified sol-gel procedure: V/MgO, V/SiO2, and vanadium phosphate (VPO). These represent active oxidation catalysts for a number of industrially relevant reactions. The catalysts were characterized by x-ray diffraction and Raman, UV-VIS, infrared and x-ray absorption spectroscopies with the goal of determining the primary structural and chemical differences between nanocrystals and microcrystals. The catalytic activity of these catalysts was also studied in oxidative dehydrogenation of butane and methanol oxidation to formaldehyde. V/MgO nanocrystals were investigated for activity in oxidative dehydrogenation of butane and compared to conventional V/MgO catalysts. Characterization of V/MgO catalysts using Raman spectroscopy and x-ray absorption spectroscopy showed that both types of catalysts contained magnesium orthovanadate at vanadium loadings below 15 weight%, but above that loading, magnesium pyrovanadate may have been present. In general, MgO nanocrystals had roughly half the crystal size and double the surface area of the conventional MgO. In oxidative dehydrogenation of butane, nanocrystalline V/MgO gave higher selectivity to butene than conventional V/MgO at the same conversion. This difference was attributed to differences in vanadium domain size resulting from the higher surface areas of the nanocrystalline support, since characterization suggested that similar vanadium phases were present on both types of catalysts. Experiments in methanol oxidation were used to probe the chemical differences between sol-gel prepared and conventionally prepared metal oxides. Both V/MgO and V/SiO2 were studied. For both catalysts, similar product selectivities were noted for either preparation method, suggesting similar acid/base and redox properties for the catalysts. At lower weight loadings (<5%), activity was also similar, but at higher weight loadings the sol-gel prepared catalysts were more active. This was attributed to the greater dispersion of vanadium on sol-gel prepared catalysts, and it was suggested that small vanadium oxide domains were more active in methanol oxidation than polymeric and bulk domains. A novel sol-gel method was developed for preparation of VPO catalysts, which are used industrially in butane oxidation to maleic anhydride. In this method vanadium (V) triisopropoxide was reacted with orthophosphoric acid in THF to form a gel. Drying this gel under air resulted in an intercalated VOPO4 compound, where solvent molecules were trapped between layers of the vanadium phosphate compound. Higher surface areas could be achieved by drying this gel at high pressure in an autoclave. The amount of solvent (THF) placed in the autoclave was important in this process. Low amounts of solvent led to a lower surface area, as the solvent evaporated before reaching the critical point and collapsed the gel's pores. In addition, vanadium reduction occurred in the autoclave due to reaction of isopropanol with the vanadium phosphate. Higher amounts of THF reduced the concentration of isopropanol, leading to less reduction. Surfaces areas in excess of 100 m2/g were achieved with this method, and the product was confirmed through XPS and IR to be VOHPO4*0.5H2O, the common precursor for industrial VPO catalysts. Furthermore, this product displayed a platelet morphology, which is desirable for butane oxidation. Further work showed that this material could be transformed to (VO)2P2O7 (the industrial catalyst for butane oxidation to maleic anhydride) by heating under nitrogen without losing much surface are

  2. Trends in Methanol Decomposition on Transition Metal Alloy Clusters from Scaling and BrnstedEvansPolanyi Relationships

    SciTech Connect (OSTI)

    Mehmood, Faisal; Rankin, Rees B.; Greeley, Jeffrey P.; Curtiss, Larry A.

    2012-05-15

    A combination of ?rst principles Density Functional Theory calculations and thermochemical scaling relationships are employed to estimate the thermochemistry and kinetics of methanol decomposition on unsupported subnanometer metal clusters. The approach uses binding energies of various atomic and molecular species, determined on the pure metal clusters, to develop scaling relationships that are then further used to estimate the methanol decomposition thermodynamics for a series of pure and bimetallic clusters with four atoms per cluster. Additionally, activation energy barriers are estimated from BrnstedEvansPolanyi plots relating transition and ?nal state energies on these clusters. The energetic results are combined with a simple, microkineticallyinspired rate expression to estimate reaction rates as a function of important catalytic descriptors, including the carbon and atomic oxygen binding energies to the clusters. Based on these analyses, several alloy clusters are identi?ed as promising candidates for the methanol decomposition reaction.

  3. Long-term, low-temperature oxidation of PWR spent fuel: Interim transition report

    SciTech Connect (OSTI)

    Einziger, R.E.; Buchanan, H.C.

    1988-05-01

    Since some of the fuel rods will be breached and eventually most of the cladding will corrode, exposing fuel, one factor influencing the ability of spent fuel to retain radionuclides is its oxidation state in the expected moist air atmosphere. Oxidation of the fuel could split the cladding, exposing additional fuel and changing the leaching characteristics. Thermodynamically, there is no reason why UO{sub 2} should not oxidize completely to UO{sub 3} at repository temperatures. The underlying uncertainty is the rate of oxidation. Extrapolation of higher temperature data indicates that insufficient oxidation to convert all of the fuel to U{sub 3}O{sub 8} will occur during the first 10,000 years. However, lower oxidation states, such as U{sub 4}O{sub 9} and U{sub 3}O{sub 7}, might form. To date, the tests have run between 3200 and 4100 hours out of a planned 16,000-hour duration. Some preliminary conclusions can be drawn: (1) Moisture content of the air has no significant effect on oxidation rate, (2) the data have an uncertainty of 15 to 20%, which must be accounted for in the interpretation of single sample tests, and (3) below 175{degree}C, the oxidation rate is dependent on the particle size in the sample. The smaller particles oxidize more rapidly. 19 refs., 23 figs., 7 tabs.

  4. Kinetics of solid-solid phase transitions in metals using proton radiography (u)

    SciTech Connect (OSTI)

    Schwartz, Cynthia L; Rigg, Paulo A; Hixson, Rob S; Jensen, Brian J

    2011-01-25

    When a compressed material changes phase it doesn't do so instantly. Instead it transitions through a mixed phase as it transforms to the end state phase for a given pressure, volume and temperature. Common phase diagrams show the phase boundaries as sharp lines when compression has been slowly applied and held for an infinite amount of time. When the compression is applied with high strain rate, however, the phase boundaries are no longer crisp as the kinetic effects of the crystal reorientation delay the transitions, resulting in regions of mixed phase. This opens up the possibility that some degree of metastability exists for such transition in dynamic compression. The compression path can go past the equilibrium phase boundary and the transition happen from a metastable state because of the very short timescale of the compression process. Molecular dynamics (MD) simulations recently have been used to examine shock-induced phase transitions in single crystal materials illustrating an orientation dependence of the transition stress, mechanisms, kinetics, and Hugoniot response. For example, the [100] orientation of iron had a simulated transition stress higher than the experimentally determined polycrystalline value of 13 GPa by 2 GPa. Previously, dynamic experiments on iron have observed a non-zero transition time and width in the solid-solid {alpha}-{var_epsilon} phase transition. Using Proton Radiography at the Los Alamos Neutron Science Center, we have performed plate impact experiments on iron to further study the {alpha}-{var_epsilon} phase transition which occurs at 13 GPa. A 40mm bore powder gun was coupled to a proton radiography beam line and imaging system and synchronized to the impact of the projectile on the target sample with the proton beam pattern. A typical experimental configuration for the iron study, as shown below in 3 color-enhanced radiographs, is a 40mm diameter aluminum sabot impacting a 40mm diameter sample of polycrystalline ARMCO iron. The iron is backed by a sapphire optical window for velocimetry measurements. The aluminum flyer on the left of the iron is barely visible for visual display purposes.

  5. Porphyrins and metal complexes thereof having haloalkyl side chains

    DOE Patents [OSTI]

    Wijesekera, T.; Lyons, J.E.; Ellis, P.E. Jr.; Bhinde, M.V.

    1997-03-04

    Transition metal complexes of meso-haloalkylporphyrins, wherein the haloalkyl groups contain 2 to 8 carbon atoms have been found to be highly effective catalysts for oxidation of alkanes and for the decomposition of hydroperoxides. 7 figs.

  6. Porphyrins and metal complexes thereof having haloalkyl side chains

    DOE Patents [OSTI]

    Wijesekera, Tilak; Lyons, James E.; Ellis, Jr., Paul E.; Bhinde, Manoj V.

    1997-01-01

    Transition metal complexes of meso-haloalkylporphyrins, wherein the haloalkyl groups contain 2 to 8 carbon atoms have been found to be highly effective catalysts for oxidation of alkanes and for the decomposition of hydroperoxides.

  7. Process for making whiskers, fibers and flakes of transition metal compounds

    DOE Patents [OSTI]

    Bamberger, Carlos E. (Oak Ridge, TN)

    1992-01-01

    A process for making titanium and chromium nitrides of known morphology by reacting potassium titanate and chromium oxide in the gas phase with NH.sub.3. The products exhibit the same morphology as the starting material.

  8. Process for making whiskers, fibers and flakes of transition metal compounds

    DOE Patents [OSTI]

    Bamberger, C.E.

    1992-06-02

    A process for making titanium and chromium nitrides of known morphology by reacting potassium titanate and chromium oxide in the gas phase with NH[sub 3]. The products exhibit the same morphology as the starting material.

  9. Promises and Challenges of Lithium- and Manganese-Rich Transition-Metal Layered-Oxide Cathodes

    Broader source: Energy.gov [DOE]

    2013 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting

  10. Method for producing metal oxide aerogels having densities less than 0.02 g/cc

    DOE Patents [OSTI]

    Tillotson, Thomas M. (Tracy, CA); Poco, John F. (Livermore, CA); Hrubesh, Lawrence W. (Pleasanton, CA); Thomas, Ian M. (Livermore, CA)

    1994-01-01

    A two-step method is described for making transparent aerogels which have a density of less than 0.003 g/cm.sup.3 to those with a density of more than 0.8 g/cm.sup.3, by a sol/gel process and supercritical extraction. Condensed metal oxide intermediate made with purified reagents can be diluted to produce stable aerogels with a density of less than 0.02 g/cm.sup.3. High temperature, direct supercritical extraction of the liquid phase of the gel produces hydrophobic aerogels which are stable at atmospheric moisture conditions. Monolithic, homogeneous silica aerogels with a density of less than 0.02 to higher than 0.8 g/cm.sup.3, with high thermal insulation capacity, improved mechanical strength and good optical transparency, are described.

  11. Method for producing metal oxide aerogels having densities less than 0. 02 g/cc

    DOE Patents [OSTI]

    Tillotson, T.M.; Poco, J.F.; Hrubesh, L.W.; Thomas, I.M.

    1994-01-04

    A two-step method is described for making transparent aerogels which have a density of less than 0.003 g/cm[sup 3] to those with a density of more than 0.8 g/cm[sup 3], by a sol/gel process and supercritical extraction. Condensed metal oxide intermediate made with purified reagents can be diluted to produce stable aerogels with a density of less than 0.02 g/cm[sup 3]. High temperature, direct supercritical extraction of the liquid phase of the gel produces hydrophobic aerogels which are stable at atmospheric moisture conditions. Monolithic, homogeneous silica aerogels with a density of less than 0.02 to higher than 0.8 g/cm[sup 3], with high thermal insulation capacity, improved mechanical strength and good optical transparency, are described. 7 figures.

  12. HEU to LEU conversion and blending facility: Metal blending alternative to produce LEU oxide for disposal

    SciTech Connect (OSTI)

    1995-09-01

    US DOE is examining options for disposing of surplus weapons-usable fissile materials and storage of all weapons-usable fissile materials. The nuclear material is converted to a form more proliferation- resistant than the original form. Blending HEU (highly enriched uranium) with less-enriched uranium to form LEU has been proposed as a disposition option. Five technologies are being assessed for blending HEU. This document provides data to be used in environmental impact analysis for the HEU-LEU disposition option that uses metal blending with an oxide waste product. It is divided into: mission and assumptions, conversion and blending facility descriptions, process descriptions and requirements, resource needs, employment needs, waste and emissions from plant, hazards discussion, and intersite transportation.

  13. Transient radiation hardened CMOS (complementary metal oxide semiconductor) operational amplifiers. Master's thesis

    SciTech Connect (OSTI)

    Trombley, G.J.

    1989-01-01

    General strategies are developed for designing radiation hardened bulk and silicon on insulator (SOI) complementary metal oxide semiconductor (CMOS) operational amplifiers. Comparisons are made between each technology concerning photocurrent mechanisms and the inherent advantages of SOI CMOS. Methods are presented for analysing circuit designs and minimizing the net photocurrent responses. Analysis is performed on standard operational amplifier circuits and subcircuits to demonstrate the usefulness of these methods. Radiation hardening topics discussed include superior radiation hardened topologies, photocurrent compensation and its limitations, and methods to ensure a preferred direction of photocurrent response. Several operational amplifier subcircuits are compared for their hardness characteristics. Folded cascode and three-stage operational amplifiers were fabricated on an SOI CMOS test chip supported by Texas Instruments, Incorporated. At the time of publication, the circuit operation was verified but radiation data were not yet available.

  14. Process for improving metal production in steelmaking processes

    DOE Patents [OSTI]

    Pal, U.B.; Gazula, G.K.M.; Hasham, A.

    1996-06-18

    A process and apparatus for improving metal production in ironmaking and steelmaking processes is disclosed. The use of an inert metallic conductor in the slag containing crucible and the addition of a transition metal oxide to the slag are the disclosed process improvements. 6 figs.

  15. Process for improving metal production in steelmaking processes

    DOE Patents [OSTI]

    Pal, Uday B. (Malden, MA); Gazula, Gopala K. M. (Somerville, MA); Hasham, Ali (Karachi, PK)

    1996-01-01

    A process and apparatus for improving metal production in ironmaking and steelmaking processes is disclosed. The use of an inert metallic conductor in the slag containing crucible and the addition of a transition metal oxide to the slag are the disclosed process improvements.

  16. Sub-Nanostructured Non Transition Metal Complex Grids for Hydrogen Storage

    SciTech Connect (OSTI)

    Dr. Orhan Talu; Dr. Surendra N. Tewari

    2007-10-27

    This project involved growing sub-nanostructured metal grids to increase dynamic hydrogen storage capacity of metal hydride systems. The nano particles of any material have unique properties unlike its bulk form. Nano-structuring metal hydride materials can result in: {sm_bullet}Increased hydrogen molecule dissociation rate, {sm_bullet} Increased hydrogen atom transport rate, {sm_bullet} Decreased decrepitation caused by cycling, {sm_bullet} Increased energy transfer in the metal matrix, {sm_bullet} Possible additional contribution by physical adsorption, and {sm_bullet} Possible additional contribution by quantum effects The project succeeded in making nano-structured palladium using electrochemical growth in templates including zeolites, mesoporous silica, polycarbonate films and anodized alumina. Other metals were used to fine-tune the synthesis procedures. Palladium was chosen to demonstrate the effects of nano-structuring since its bulk hydrogen storage capacity and kinetics are well known. Reduced project funding was not sufficient for complete characterization of these materials for hydrogen storage application. The project team intends to seek further funding in the future to complete the characterization of these materials for hydrogen storage.

  17. Correlating the chemical composition and size of various metal oxide substrates with the catalytic activity and stability of as-deposited Pt nanoparticles for the methanol oxidation reaction

    SciTech Connect (OSTI)

    Megan E. Scofield; Wong, Stanislaus S.; Koenigsmann, Christopher; Bobb-Semple, Dara; Tao, Jing; Tong, Xiao; Wang, Lei; Lewis, Crystal S.; Vuklmirovic, Miomir; Zhu, Yimei; Adzic, Radoslav R.

    2015-12-09

    The performance of electrode materials in conventional direct alcohol fuel cells (DAFC) is constrained by (i) the low activity of the catalyst materials relative to their overall cost, (ii) the poisoning of the active sites due to the presence of partially oxidized carbon species (such as but not limited to CO, formate, and acetate) produced during small molecule oxidation, and (iii) the lack of catalytic stability and durability on the underlying commercial carbon support. Therefore, as a viable alternative, we have synthesized various metal oxide and perovskite materials of different sizes and chemical compositions as supports for Pt nanoparticles (NPs). Our results including unique mechanistic studies demonstrate that the SrRuO3 substrate with immobilized Pt NPs at its surface evinces the best methanol oxidation performance as compared with all of the other substrate materials tested herein, including commercial carbon itself. In addition, data from electron energy loss spectroscopy (EELS) and X-ray photoelectron spectroscopy (XPS) confirmed the presence of electron transfer from bound Pt NPs to surface Ru species within the SrRuO3 substrate itself, thereby suggesting that favorable metal support interactions are responsible for the increased methanol oxidation reaction (MOR) activity of Pt species with respect to the underlying SrRuO3 composite catalyst material.

  18. Correlating the chemical composition and size of various metal oxide substrates with the catalytic activity and stability of as-deposited Pt nanoparticles for the methanol oxidation reaction

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Megan E. Scofield; Wong, Stanislaus S.; Koenigsmann, Christopher; Bobb-Semple, Dara; Tao, Jing; Tong, Xiao; Wang, Lei; Lewis, Crystal S.; Vuklmirovic, Miomir; Zhu, Yimei; et al

    2015-12-09

    The performance of electrode materials in conventional direct alcohol fuel cells (DAFC) is constrained by (i) the low activity of the catalyst materials relative to their overall cost, (ii) the poisoning of the active sites due to the presence of partially oxidized carbon species (such as but not limited to CO, formate, and acetate) produced during small molecule oxidation, and (iii) the lack of catalytic stability and durability on the underlying commercial carbon support. Therefore, as a viable alternative, we have synthesized various metal oxide and perovskite materials of different sizes and chemical compositions as supports for Pt nanoparticles (NPs).more » Our results including unique mechanistic studies demonstrate that the SrRuO3 substrate with immobilized Pt NPs at its surface evinces the best methanol oxidation performance as compared with all of the other substrate materials tested herein, including commercial carbon itself. In addition, data from electron energy loss spectroscopy (EELS) and X-ray photoelectron spectroscopy (XPS) confirmed the presence of electron transfer from bound Pt NPs to surface Ru species within the SrRuO3 substrate itself, thereby suggesting that favorable metal support interactions are responsible for the increased methanol oxidation reaction (MOR) activity of Pt species with respect to the underlying SrRuO3 composite catalyst material.« less

  19. Large scale simulations of the mechanical properties of layered transition metal ternary compounds for fossil energy power system applications

    SciTech Connect (OSTI)

    Ching, Wai-Yim

    2014-12-31

    Advanced materials with applications in extreme conditions such as high temperature, high pressure, and corrosive environments play a critical role in the development of new technologies to significantly improve the performance of different types of power plants. Materials that are currently employed in fossil energy conversion systems are typically the Ni-based alloys and stainless steels that have already reached their ultimate performance limits. Incremental improvements are unlikely to meet the more stringent requirements aimed at increased efficiency and reduce risks while addressing environmental concerns and keeping costs low. Computational studies can lead the way in the search for novel materials or for significant improvements in existing materials that can meet such requirements. Detailed computational studies with sufficient predictive power can provide an atomistic level understanding of the key characteristics that lead to desirable properties. This project focuses on the comprehensive study of a new class of materials called MAX phases, or Mn+1AXn (M = a transition metal, A = Al or other group III, IV, and V elements, X = C or N). The MAX phases are layered transition metal carbides or nitrides with a rare combination of metallic and ceramic properties. Due to their unique structural arrangements and special types of bonding, these thermodynamically stable alloys possess some of the most outstanding properties. We used a genomic approach in screening a large number of potential MAX phases and established a database for 665 viable MAX compounds on the structure, mechanical and electronic properties and investigated the correlations between them. This database if then used as a tool for materials informatics for further exploration of this class of intermetallic compounds.

  20. Inverse Design of Mn-based ternary p-type wide-gap oxides

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    used theory to predict band structure and transport properties for the d 5 transition metal (TM) oxides MnO and Fe 2 O 3 . Significance and Impact This work identified design principles for improving d 5 oxides as a new class of semiconductors with potential applications in energy conversion. Design Principles Demonstrated for Semiconducting d 5 Transition-Metal Oxides with Photovoltaic Applications Potential H. Peng and S. Lany, Phys. Rev. B (Rapid Comm.) 85, 201202(R) (2012). Figure 1:

  1. Coherent orbital waves during an Ultrafast Photo-induced Isulator-metal Transition in a magnetoresistive manganite

    SciTech Connect (OSTI)

    ULTRAS-INFM-CNR Dipartimento di Fisica, Politecnico di Milano, Italy; Department of Physics - Cavalleri Group, Clarendon Laboratory, University of Oxford, U.K.; Correlated Electron Research Center, Tsukuba, Japan; Schoenlein, Robert William; Polli, D.; Rini, M.; Wall, S.; Schoenlein, R.W.; Tomioka, Y.; Tokura, Y.; Cerullo, G.; Cavalleri, A.

    2007-06-01

    Photo-excitation can drive strongly correlated electron insulators into competing conducting phases1,2, resulting in giant and ultrafast changes of their electronic and magnetic properties. The underlying non-equilibrium dynamics involve many degrees of freedom at once, whereby sufficiently short optical pulses can trigger the corresponding collective modes of the solid along temporally coherent pathways. The characteristic frequencies of these modes range between the few GHz of acoustic vibrations3 to the tens or even hundreds of THz for purely electronic excitations. Virtually all experiments so far have used 100 fs or longer pulses, detecting only comparatively slow lattice dynamics4,5. Here, we use sub-10-fs optical pulses to study the photo-induced insulator-metal transition in the magneto-resistive manganite Pr0.7Ca0.3MnO3. At room temperature, we find that the time-dependent pathway towards the metallic phase is accompanied by coherent 31 THz oscillations of the optical reflectivity, significantly faster than all lattice vibrations. These high-frequency oscillations are suggestive of coherent orbital waves6,7, crystal-field excitations triggered here by impulsive stimulated Raman scattering. Orbital waves are likely to be initially localized to the small polarons of this room-temperature manganite, coupling to other degrees of freedom at longer times, as photo-domains coalesce into a metallic phase.

  2. Variation of the shape and morphological properties of silica and metal oxide powders by electro homogeneous precipitation

    DOE Patents [OSTI]

    Harris, M.T.; Basaran, O.A.; Sisson, W.G.; Brunson, R.R.

    1997-02-18

    The present invention provides a method for preparing irreversible linear aggregates (fibrils) of metal oxide powders by utilizing static or pulsed DC electrical fields across a relatively non-conducting liquid solvent in which organometal compounds or silicon alkoxides have been dissolved. The electric field is applied to the relatively non-conducting solution throughout the particle formation and growth process promoting the formation of either linear aggregates (fibrils) or spherical shaped particles as desired. Thus the present invention provides a physical method for altering the size, shape and porosity of precursor hydrous metal oxide or hydrous silicon oxide powders for the development of advanced ceramics with improved strength and insulating capacity. 3 figs.

  3. Site-Specific Scaling Relations for Hydrocarbon Adsorption on Hexagonal Transition Metal Surfaces

    SciTech Connect (OSTI)

    Montemore, Matthew M.; Medlin, James W.

    2013-10-03

    Screening a large number of surfaces for their catalytic performance remains a challenge, leading to the need for simple models to predict adsorption properties. To facilitate rapid prediction of hydrocarbon adsorption energies, scaling relations that allow for calculation of the adsorption energy of any intermediate attached to any symmetric site on any hexagonal metal surface through a carbon atom were developed. For input, these relations require only simple electronic properties of the surface and of the gas-phase reactant molecules. Determining adsorption energies consists of up to four steps: (i) calculating the adsorption energy of methyl in the top site using density functional theory or by simple relations based on the electronic structure of the surface; (ii) using modified versions of classical scaling relations to scale between methyl in the top site and C? species with more metal-surface bonds (i.e., C, CH, CH?) in sites that complete adsorbate tetravalency; (iii) using gas-phase bond energies to predict adsorption energies of longer hydrocarbons (i.e., CR, CR?, CR?); and (iv) expressing energetic changes upon translation of hydrocarbons to various sites in terms of the number of agostic interactions and the change in the number of carbon-metal bonds. Combining all of these relations allows accurate scaling over a wide range of adsorbates and surfaces, resulting in efficient screening of catalytic surfaces and a clear elucidation of adsorption trends. The relations are used to explain trends in methane reforming, hydrocarbon chain growth, and propane dehydrogenation.

  4. The transformation of organic amines by transition metal cluster compounds: Progress report

    SciTech Connect (OSTI)

    Adams, R.D.

    1994-11-01

    Research during the current award period has covered several related topics which have emerged and grown as a consequence of the various discoveries that have been made during this award period. They have been divided into the following subsections for clarity and emphasis: The activation of tertiary amines by osmium cluster complexes; CH bond activation and ring opening of a nitrogen containing strained ring heterocycle by an osmium cluster complex; Ring opening of cyclic thioethers; cyclooligomerization of Thietanes; Studies of the cyclobutyne ligand; Insertion of an alkynes into metal-metal bonds; and Energy storage in metal clusters. A summary of the results of these studies is given in the following sections of this report. These studies have resulted in 50 scientific publications over the last three years and details of their studies beyond that given in the following sections can be found in those reports. All of these reports are listed in the final section of this report by the author`s names, title and journal citation.

  5. Electric double layer at metal oxide surfaces: Static properties of the cassiterite - Water Interface

    SciTech Connect (OSTI)

    Vlcek, Lukas; Zhang, Zhan; Machesky, Michael L.; Wesolowski, David J

    2007-04-01

    The structure of water at the (110) surface of cassiterite ({alpha}-SnO{sub 2}) at ambient conditions was studied by means of molecular dynamics simulations and X-ray crystal truncation rod experiments and interpreted with the help of the revised MUSIC model of surface protonation. The interactions of the metal oxide in the simulations were described by a recently developed classical force field based on the SPC/E model of water. Two extreme cases of completely hydroxylated and nonhydroxylated surfaces were considered along with a mixed surface with 50% dissociation. To study the dependence of the surface properties on pH, neutral and negatively charged variants of the surfaces were constructed. Axial and lateral density distributions of water for different types of surfaces were compared to each other and to experimental axial density distributions found by X-ray experiments. Although significant differences were found between the structures of the studied interfaces, the axial distances between Sn and O atoms are very similar and therefore could not be clearly distinguished by the diffraction technique. The explanation of structures observed in the density distributions was provided by a detailed analysis of hydrogen bonding in the interfacial region. It revealed qualitatively different hydrating patterns formed at neutral hydroxylated and nonhydroxylated surfaces and suggested a preference for the dissociative adsorption of water. At negatively charged surfaces, however, the situation can be reversed by the electric field stabilizing a hydrogen bond network similar to that found at the neutral nonhydroxylated surface. Comparison with previously studied rutile ({alpha}-TiO{sub 2}) surfaces provided insight into the differences between the hydration of these two metal oxides, and an important role was ascribed to their different lattice parameters. A link to macroscopic properties was provided by the revised MUSIC surface protonation model. Explicit use of the Sn-O bond lengths based on ab initio calculations and H-bond configurations as inputs led to the prediction of a pH of zero net-proton induced surface charge (pH{sub pzc}) that agrees very well with those determined experimentally (about 4.4 at 298 K).

  6. Electric double layer at metal oxide surfaces:static properties of the cassiterite-water interface.

    SciTech Connect (OSTI)

    Vlcek, L.; Zhang, Z.; Machesky, M .L.; Fenter, P.; Rosenqvist, J.; Wesolowski, D. J.; Anovitz, L. M.; Predota, M.; Cummings, P. T.; Vanderbilt Univ.; ORNL; Univ. of South Bohimia; Illinois State Water Survey

    2007-03-24

    The structure of water at the (110) surface of cassiterite ({alpha}-SnO{sub 2}) at ambient conditions was studied by means of molecular dynamics simulations and X-ray crystal truncation rod experiments and interpreted with the help of the revised MUSIC model of surface protonation. The interactions of the metal oxide in the simulations were described by a recently developed classical force field based on the SPC/E model of water. Two extreme cases of completely hydroxylated and nonhydroxylated surfaces were considered along with a mixed surface with 50% dissociation. To study the dependence of the surface properties on pH, neutral and negatively charged variants of the surfaces were constructed. Axial and lateral density distributions of water for different types of surfaces were compared to each other and to experimental axial density distributions found by X-ray experiments. Although significant differences were found between the structures of the studied interfaces, the axial distances between Sn and O atoms are very similar and therefore could not be clearly distinguished by the diffraction technique. The explanation of structures observed in the density distributions was provided by a detailed analysis of hydrogen bonding in the interfacial region. It revealed qualitatively different hydrating patterns formed at neutral hydroxylated and nonhydroxylated surfaces and suggested a preference for the dissociative adsorption of water. At negatively charged surfaces, however, the situation can be reversed by the electric field stabilizing a hydrogen bond network similar to that found at the neutral nonhydroxylated surface. Comparison with previously studied rutile ({alpha}-TiO{sub 2}) surfaces provided insight into the differences between the hydration of these two metal oxides, and an important role was ascribed to their different lattice parameters. A link to macroscopic properties was provided by the revised MUSIC surface protonation model. Explicit use of the Sn-O bond lengths based on ab initio calculations and H-bond configurations as inputs led to the prediction of a pH of zero net-proton induced surface charge (pH{sub pzc}) that agrees very well with those determined experimentally (about 4.4 at 298 K).

  7. Structural evolution across the insulator-metal transition in oxygen-deficient BaTiO3-δ studied using neutron total scattering and Rietveld analysis

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Jeong, I.-K.; Lee, Seunghun; Jeong, Se-Young; Won, C. J.; Hur, N.; Llobet, A.

    2011-08-29

    Oxygen-deficient BaTiO3-δ exhibits an insulator-metal transition with increasing δ. We performed neutron total scattering measurements to study structural evolution across an insulator-metal transition in BaTiO3-δ. Despite its significant impact on resistivity, slight oxygen reduction (δ=0.09) caused only a small disturbance on the local doublet splitting of Ti-O bond. This finding implies that local polarization is well preserved under marginal electric conduction. In the highly oxygen-deficient metallic state (δ=0.25), however, doublet splitting of the Ti-O bond became smeared. The smearing of the local Ti-O doublet is complemented with long-range structural analysis and demonstrates that the metallic conduction in the highly oxygen-reducedmore » BaTiO3-δ is due to the appearance of nonferroelectric cubic lattice.« less

  8. Hydrogen incorporation induced metal-semiconductor transition in ZnO:H thin films sputtered at room temperature

    SciTech Connect (OSTI)

    Singh, Anil; Chaudhary, Sujeet; Pandya, D. K.

    2013-04-29

    The room temperature deposited ZnO:H thin films having high conductivity of 500 Ohm-Sign {sup -1} cm{sup -1} and carrier concentration reaching 1.23 Multiplication-Sign 10{sup 20} cm{sup -3} were reactively sputter deposited on glass substrates in the presence of O{sub 2} and 5% H{sub 2} in Ar. A metal-semiconductor transition at 165 K is induced by the increasing hydrogen incorporation in the films. Hydrogen forms shallow donor complex with activation energy of {approx}10-20 meV at oxygen vacancies (V{sub O}) leading to increase in carrier concentration. Hydrogen also passivates V{sub O} and V{sub Zn} causing {approx}4 times enhancement of mobility to 25.4 cm{sup 2}/V s. These films have potential for use in transparent flexible electronics.

  9. Large-Scale Synthesis of Transition-Metal-Doped TiO2 Nanowires with Controllable Overpotential

    SciTech Connect (OSTI)

    Liu, Bin; Chen, HaoMing; Liu, Chong; Andrews, Sean; Han, Chris; Yang, Peidong

    2013-03-13

    Practical implementation of one-dimensional semiconductors into devices capable of exploiting their novel properties is often hindered by low product yields, poor material quality, high production cost, or overall lack of synthetic control. Here, we show that a molten-salt flux scheme can be used to synthesize large quantities of high-quality, single-crystalline TiO2 nanowires with controllable dimensions. Furthermore, in situ dopant incorporation of various transition metals allows for the tuning of optical, electrical, and catalytic properties. With this combination of control, robustness, and scalability, the molten-salt flux scheme can provide high-quality TiO2 nanowires to satisfy a broad range of application needs from photovoltaics to photocatalysis.

  10. Rapid low-temperature processing of metal-oxide thin film transistors with combined far ultraviolet and thermal annealing

    SciTech Connect (OSTI)

    Leppniemi, J. Ojanper, K.; Kololuoma, T.; Huttunen, O.-H.; Majumdar, H.; Alastalo, A.; Dahl, J.; Tuominen, M.; Laukkanen, P.

    2014-09-15

    We propose a combined far ultraviolet (FUV) and thermal annealing method of metal-nitrate-based precursor solutions that allows efficient conversion of the precursor to metal-oxide semiconductor (indium zinc oxide, IZO, and indium oxide, In{sub 2}O{sub 3}) both at low-temperature and in short processing time. The combined annealing method enables a reduction of more than 100?C in annealing temperature when compared to thermally annealed reference thin-film transistor (TFT) devices of similar performance. Amorphous IZO films annealed at 250?C with FUV for 5?min yield enhancement-mode TFTs with saturation mobility of ?1?cm{sup 2}/(Vs). Amorphous In{sub 2}O{sub 3} films annealed for 15?min with FUV at temperatures of 180?C and 200?C yield TFTs with low-hysteresis and saturation mobility of 3.2?cm{sup 2}/(Vs) and 7.5?cm{sup 2}/(Vs), respectively. The precursor condensation process is clarified with x-ray photoelectron spectroscopy measurements. Introducing the FUV irradiation at 160?nm expedites the condensation process via in situ hydroxyl radical generation that results in the rapid formation of a continuous metal-oxygen-metal structure in the film. The results of this paper are relevant in order to upscale printed electronics fabrication to production-scale roll-to-roll environments.

  11. Probing the structural dependency of photoinduced properties of colloidal quantum dots using metal-oxide photo-active substrates

    SciTech Connect (OSTI)

    Patty, Kira; Campbell, Quinn; Hamilton, Nathan; West, Robert G.; Sadeghi, Seyed M.; Mao, Chuanbin

    2014-09-21

    We used photoactive substrates consisting of about 1 nm coating of a metal oxide on glass substrates to investigate the impact of the structures of colloidal quantum dots on their photophysical and photochemical properties. We showed during irradiation these substrates can interact uniquely with such quantum dots, inducing distinct forms of photo-induced processes when they have different cores, shells, or ligands. In particular, our results showed that for certain types of core-shell quantum dot structures an ultrathin layer of a metal oxide can reduce suppression of quantum efficiency of the quantum dots happening when they undergo extensive photo-oxidation. This suggests the possibility of shrinking the sizes of quantum dots without significant enhancement of their non-radiative decay rates. We show that such quantum dots are not influenced significantly by Coulomb blockade or photoionization, while those without a shell can undergo a large amount of photo-induced fluorescence enhancement via such blockade when they are in touch with the metal oxide.

  12. Trends in Formic Acid Decomposition on Model Transition Metal Surfaces: A Density Functional Theory Study

    SciTech Connect (OSTI)

    Herron, Jeffrey A.; Scaranto, Jessica; Ferrin, Peter A.; Li, Sha; Mavrikakis, Manos

    2014-12-05

    We present a first-principles, self-consistent periodic density functional theory (PW91-GGA) study of formic acid (HCOOH) decomposition on model (111) and (100) facets of eight fcc metals (Au, Ag, Cu, Pt, Pd, Ni, Ir, and Rh) and (0001) facets of four hcp (Co, Os, Ru, and Re) metals. The calculated binding energies of key formic acid decomposition intermediates including formate (HCOO), carboxyl (COOH), carbon monoxide (CO), water (H2O), carbon dioxide (CO2), hydroxyl (OH), carbon (C), oxygen (O), and hydrogen (H; H2) are presented. Using these energetics, we develop thermochemical potential energy diagrams for both the carboxyl-mediated and the formate-mediated dehydrogenation mechanisms on each surface. We evaluate the relative stability of COOH, HCOO, and other isomeric intermediates (i.e., CO + OH, CO2 + H, CO + O + H) on these surfaces. These results provide insights into formic acid decomposition selectivity (dehydrogenation versus dehydration), and in conjunction with calculated vibrational frequency modes, the results can assist with the experimental search for the elusive carboxyl (COOH) surface intermediate. Results are compared against experimental reports in the literature.

  13. Ultraviolet GaN photodetectors on Si via oxide buffer heterostructures with integrated short period oxide-based distributed Bragg reflectors and leakage suppressing metal-oxide-semiconductor contacts

    SciTech Connect (OSTI)

    Szyszka, A. E-mail: adam.szyszka@pwr.wroc.pl; Haeberlen, M.; Storck, P.; Thapa, S. B.; Schroeder, T.

    2014-08-28

    Based on a novel double step oxide buffer heterostructure approach for GaN integration on Si, we present an optimized Metal-Semiconductor-Metal (MSM)-based Ultraviolet (UV) GaN photodetector system with integrated short-period (oxide/Si) Distributed Bragg Reflector (DBR) and leakage suppressing Metal-Oxide-Semiconductor (MOS) electrode contacts. In terms of structural properties, it is demonstrated by in-situ reflection high energy electron diffraction and transmission electron microscopy-energy dispersive x-ray studies that the DBR heterostructure layers grow with high thickness homogeneity and sharp interface structures sufficient for UV applications; only minor Si diffusion into the Y{sub 2}O{sub 3} films is detected under the applied thermal growth budget. As revealed by comparative high resolution x-ray diffraction studies on GaN/oxide buffer/Si systems with and without DBR systems, the final GaN layer structure quality is not significantly influenced by the growth of the integrated DBR heterostructure. In terms of optoelectronic properties, it is demonstrated thatwith respect to the basic GaN/oxide/Si system without DBRthe insertion of (a) the DBR heterostructures and (b) dark current suppressing MOS contacts enhances the photoresponsivity below the GaN band-gap related UV cut-off energy by almost up to two orders of magnitude. Given the in-situ oxide passivation capability of grown GaN surfaces and the one order of magnitude lower number of superlattice layers in case of higher refractive index contrast (oxide/Si) systems with respect to classical III-N DBR superlattices, virtual GaN substrates on Si via functional oxide buffer systems are thus a promising robust approach for future GaN-based UV detector technologies.

  14. Comprehensive study and design of scaled metal/high-k/Ge gate stacks with ultrathin aluminum oxide interlayers

    SciTech Connect (OSTI)

    Asahara, Ryohei; Hideshima, Iori; Oka, Hiroshi; Minoura, Yuya; Hosoi, Takuji Shimura, Takayoshi; Watanabe, Heiji; Ogawa, Shingo; Yoshigoe, Akitaka; Teraoka, Yuden

    2015-06-08

    Advanced metal/high-k/Ge gate stacks with a sub-nm equivalent oxide thickness (EOT) and improved interface properties were demonstrated by controlling interface reactions using ultrathin aluminum oxide (AlO{sub x}) interlayers. A step-by-step in situ procedure by deposition of AlO{sub x} and hafnium oxide (HfO{sub x}) layers on Ge and subsequent plasma oxidation was conducted to fabricate Pt/HfO{sub 2}/AlO{sub x}/GeO{sub x}/Ge stacked structures. Comprehensive study by means of physical and electrical characterizations revealed distinct impacts of AlO{sub x} interlayers, plasma oxidation, and metal electrodes serving as capping layers on EOT scaling, improved interface quality, and thermal stability of the stacks. Aggressive EOT scaling down to 0.56 nm and very low interface state density of 2.4 × 10{sup 11 }cm{sup −2}eV{sup −1} with a sub-nm EOT and sufficient thermal stability were achieved by systematic process optimization.

  15. Investigation of Some Transparent Metal Oxides as Damp Heat Protective Coating for CIGS Solar Cells: Preprint

    SciTech Connect (OSTI)

    Pern, F. J.; Yan, F.; Zaaunbrecher, B.; To, B.; Perkins, J.; Noufi, R.

    2012-10-01

    We investigated the protective effectiveness of some transparent metal oxides (TMO) on CIGS solar cell coupons against damp heat (DH) exposure at 85oC and 85% relative humidity (RH). Sputter-deposited bilayer ZnO (BZO) with up to 0.5-um Al-doped ZnO (AZO) layer and 0.2-um bilayer InZnO were used as 'inherent' part of device structure on CdS/CIGS/Mo/SLG. Sputter-deposited 0.2-um ZnSnO and atomic layer deposited (ALD) 0.1-um Al2O3 were used as overcoat on typical BZO/CdS/CIGS/Mo/SLG solar cells. The results were all negative -- all TMO-coated CIGS cells exhibited substantial degradation in DH. Combining the optical photographs, PL and EL imaging, SEM surface micro-morphology, coupled with XRD, I-V and QE measurements, the causes of the device degradations are attributed to hydrolytic corrosion, flaking, micro-cracking, and delamination induced by the DH moisture. Mechanical stress and decrease in crystallinity (grain size effect) could be additional degrading factors for thicker AZO grown on CdS/CIGS.

  16. Final LDRD report : metal oxide films, nanostructures, and heterostructures for solar hydrogen production.

    SciTech Connect (OSTI)

    Kronawitter, Coleman X.; Antoun, Bonnie R.; Mao, Samuel S.

    2012-01-01

    The distinction between electricity and fuel use in analyses of global power consumption statistics highlights the critical importance of establishing efficient synthesis techniques for solar fuels-those chemicals whose bond energies are obtained through conversion processes driven by solar energy. Photoelectrochemical (PEC) processes show potential for the production of solar fuels because of their demonstrated versatility in facilitating optoelectronic and chemical conversion processes. Tandem PEC-photovoltaic modular configurations for the generation of hydrogen from water and sunlight (solar water splitting) provide an opportunity to develop a low-cost and efficient energy conversion scheme. The critical component in devices of this type is the PEC photoelectrode, which must be optically absorptive, chemically stable, and possess the required electronic band alignment with the electrochemical scale for its charge carriers to have sufficient potential to drive the hydrogen and oxygen evolution reactions. After many decades of investigation, the primary technological obstacle remains the development of photoelectrode structures capable of efficient conversion of light with visible frequencies, which is abundant in the solar spectrum. Metal oxides represent one of the few material classes that can be made photoactive and remain stable to perform the required functions.

  17. Synthesis of Metal Oxide Nanomaterials for Chemical Sensors by Molecular Beam Epitaxy

    SciTech Connect (OSTI)

    Nandasiri, Manjula I.; Kuchibhatla, Satyanarayana V N T; Thevuthasan, Suntharampillai

    2013-12-01

    Since the industrial revolution, detection and monitoring of toxic matter, chemical wastes, and air pollutants has become an important environmental issue. Thus, it leads to the development of chemical sensors for various environmental applications. The recent disastrous oil spills over the near-surface of ocean due to the offshore drilling emphasize the use of chemical sensors for prevention and monitoring of the processes that might lead to these mishaps.1, 2 Chemical sensors operated on a simple principle that the sensing platform undergoes a detectable change when exposed to the target substance to be sensed. Among all the types of chemical sensors, solid state gas sensors have attracted a great deal of attention due to their advantages such as high sensitivity, greater selectivity, portability, high stability and low cost.3, 4 Especially, semiconducting metal oxides such as SnO2, TiO2, and WO3 have been widely used as the active sensing platforms in solid state gas sensors.5 For the enhanced properties of solid state gas sensors, finding new sensing materials or development of existing materials will be needed. Thus, nanostructured materials such as nanotubes,6-8 nanowires,9-11 nanorods,12-15 nanobelts,16, 17 and nano-scale thin films18-23 have been synthesized and studied for chemical sensing applications.

  18. Degradation of solid oxide fuel cell metallic interconnects in fuels containing sulfur

    SciTech Connect (OSTI)

    Ziomek-Moroz, M.; Hawk, Jeffrey A.

    2005-01-01

    Hydrogen is the main fuel for all types of fuel cells except direct methanol fuel cells. Hydrogen can be generated from all manner of fossil fuels, including coal, natural gas, diesel, gasoline, other hydrocarbons, and oxygenates (e.g., methanol, ethanol, butanol, etc.). Impurities in the fuel can cause significant performance problems and sulfur, in particular, can decrease the cell performance of fuel cells, including solid oxide fuel cells (SOFC). In the SOFC, the high (800-1000C) operating temperature yields advantages (e.g., internal fuel reforming) and disadvantages (e.g., material selection and degradation problems). Significant progress in reducing the operating temperature of the SOFC from ~1000 C to ~750 C may allow less expensive metallic materials to be used for interconnects and as balance of plant (BOP) materials. This paper provides insight on the material performance of nickel, ferritic steels, and nickel-based alloys in fuels containing sulfur, primarily in the form of H2S, and seeks to quantify the extent of possible degradation due to sulfur in the gas stream.

  19. Electrodeposited porous metal oxide films with interconnected nanoparticles applied as anode of lithium ion battery

    SciTech Connect (OSTI)

    Xiao, Anguo Zhou, Shibiao; Zuo, Chenggang; Zhuan, Yongbing; Ding, Xiang

    2014-12-15

    Highlights: Highly porous NiO film is prepared by a co-electrodeposition method. Porous NiO film is composed of interconnected nanoparticles. Porous structure is favorable for fast ion/electron transfer. Porous NiO film shows good lithium ion storage properties. - Abstract: Controllable synthesis of porous metal oxide films is highly desirable for high-performance electrochemical devices. In this work, a highly porous NiO film composed of interconnected nanoparticles is prepared by a simple co-electrodeposition method. The nanoparticles in the NiO film have a size ranging from 30 to 100 nm and construct large-quantity pores of 20120 nm. As an anode material for lithium ion batteries, the highly porous NiO film electrode delivers a high discharge capacity of 700 mA h g{sup ?1} at 0.2 C, as well as good high-rate performance. After 100 cycles at 0.2 C, a specific capacitance of 517 mA h g{sup ?1} is attained. The good electrochemical performance is attributed to the interconnected porous structure, which facilitates the diffusion of ion and electron, and provides large reaction surface area leading to improved performance.

  20. Close-To-Practice Assessment Of Meat Freshness With Metal Oxide Sensor Microarray Electronic Nose

    SciTech Connect (OSTI)

    Musatov, V. Yu.; Sysoev, V. V.; Sommer, M.; Kiselev, I.

    2009-05-23

    In this report we estimate the ability of KAMINA e-nose, based on a metal oxide sensor (MOS) microarray and Linear Discriminant Analysis (LDA) pattern recognition, to evaluate meat freshness. The received results show that, 1) one or two exposures of standard meat samples to the e-nose are enough for the instrument to recognize the fresh meat prepared by the same supplier with 100% probability; 2) the meat samples of two kinds, stored at 4 deg. C and 25 deg. C, are mutually recognized at early stages of decay with the help of the LDA model built independently under the e-nose training to each kind of meat; 3) the 3-4 training cycles of exposure to meat from different suppliers are necessary for the e-nose to build a reliable LDA model accounting for the supplier factor. This study approves that the MOS e-nose is ready to be currently utilised in food industry for evaluation of product freshness. The e-nose performance is characterized by low training cost, a confident recognition power of various product decay conditions and easy adjustment to changing conditions.

  1. Hole-induced insulator-to-metal transition in La1-xSrxCrO3 epitaxial films

    SciTech Connect (OSTI)

    Zhang, Hongliang; Du, Yingge; Sushko, Petr; Bowden, Mark E.; Shutthanandan, V.; Sallis, Shawn; Piper, Louis F. J.; Chambers, Scott A.

    2015-04-01

    We have investigated the evolution of the structural and electronic properties of La1-xSrxCrO3 (0 ? x ? 1) epitaxial films deposited by molecular beam epitaxy (MBE) using x-ray diffraction, x-ray photoemission spectroscopy, x-ray absorption spectroscopy, electrical transport, and ab initio modeling. LaCrO3 is an antiferromagnetic Mott insulator whereas stoichiometric SrCrO3 is a metal. Substituting Sr2+ for La3+ in LaCrO3 effectively dopes holes into the top of valence band, leading to Cr4+ (3d2) local electron configurations. Core-level and valence-band features monotonically shift to lower binding energy with increasing x, indicating downward movement of the Fermi level toward the valence band maximum. An insulator-to-metal like transition is observed at x ? 0. 65 even as the material becomes a p-type semiconductor at lower doping level and eventually becomes degenerately doped. Valence band x-ray photoemission spectroscopy reveals diminution of electronic state density at the top of the valence band while O K-edge x-ray absorption spectroscopy shows the development of a new unoccupied state above the Fermi level as holes are doped into LaCrO3. These results indicate a pronounced redistribution of electronic state density of states upon hole doping, a result that is also obtained by density functional theory with a Hubbard U correction.

  2. Thickness-dependent metal-insulator transition in epitaxial SrRuO? ultrathin films

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Shen, Xuan; Qiu, Xiangbiao; Su, Dong; Zhou, Shengqiang; Li., Aidong; Wu, Di

    2015-01-06

    Transport characteristics of ultrathin SrRuO? films, deposited epitaxially on TiO?-terminated SrTiO? (001) single-crystal substrates, were studied as a function of film thickness. Evolution from a metallic to an insulating behavior is observed as the film thickness decreases from 20 to 4 unit cells. In films thicker than 4 unit cells, the transport behavior obeys the Drude low temperature conductivity with quantum corrections, which can be attributed to weak localization. Fitting the data with 2-dimensional localization model indicates that electron-phonon collisions are the main inelastic relaxation mechanism. In the film of 4 unit cells in thickness, the transport behavior follows variablemorerange hopping model, indicating a strongly localized state. Magnetoresistance measurements reveal a likely magnetic anisotropy with the magnetic easy axis along the out-of-plane direction.less

  3. Thickness-dependent metal-insulator transition in epitaxial SrRuO3 ultrathin films

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Shen, Xuan; Qiu, Xiangbiao; Su, Dong; Zhou, Shengqiang; Li, Aidong; Wu, Di

    2015-01-06

    Transport characteristics of ultrathin SrRuO₃ films, deposited epitaxially on TiO₂-terminated SrTiO₃ (001) single-crystal substrates, were studied as a function of film thickness. Evolution from a metallic to an insulating behavior is observed as the film thickness decreases from 20 to 4 unit cells. In films thicker than 4 unit cells, the transport behavior obeys the Drude low temperature conductivity with quantum corrections, which can be attributed to weak localization. Fitting the data with 2-dimensional localization model indicates that electron-phonon collisions are the main inelastic relaxation mechanism. In the film of 4 unit cells in thickness, the transport behavior follows variablemore » range hopping model, indicating a strongly localized state. As a result, magnetoresistance measurements reveal a likely magnetic anisotropy with the magnetic easy axis along the out-of-plane direction.« less

  4. Geochemical Impacts of Carbon Dioxide, Brine, Trace Metal and Organic Leakage into an Unconfined, Oxidizing Limestone Aquifer

    Office of Scientific and Technical Information (OSTI)

    3 (2014) 4684 - 4707 Energy Procedia GHGT-12 Geochemical impacts of carbon dioxide, brine, trace metal and organic leakage into an unconfined, oxidizing limestone aquifer Diana H. Bacon3'* *, Zhenxue Daib, Liange Zhengc "Pacific Northwest National Laboratory, Richland, Washington, USA bLos Alamos National Laboratory, Los Alamos, New Mexico, USA cLawrence Berkeley National Laboratory, Berkeley, California, USA Abstract An important risk at CO2 storage sites is the potential for groundwater

  5. High-Temperature Zirconia Oxygen Sensor with Sealed Metal/Metal...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    High-Temperature Zirconia Oxygen Sensor with Sealed MetalMetal Oxide Internal Reference High-Temperature Zirconia Oxygen Sensor with Sealed MetalMetal Oxide Internal Reference ...

  6. Geochemical, metagenomic and metaproteomic insights into trace metal utilization by methane-oxidizing microbial consortia in sulfidic marine sediments

    SciTech Connect (OSTI)

    Glass, DR. Jennifer; Yu, DR. Hang; Steele, Joshua; Dawson, Katherine; Sun, S; Chourey, Karuna; Hettich, Robert {Bob} L; Orphan, V

    2014-01-01

    Microbes have obligate requirements for trace metals in metalloenzymes that catalyze important biogeochemical reactions. In anoxic methane- and sulfide-rich environments, microbes may have unique adaptations for metal acquisition and utilization due to decreased bioavailability as a result of metal sulfide precipitation. However, micronutrient cycling is largely unexplored in cold ( 10 C) and sulfidic (>1 mM H2S) deep-sea methane seep ecosystems. We investigated trace metal geochemistry and microbial metal utilization in methane seeps offshore Oregon and California, USA, and report dissolved concentrations of nickel (0.5-270 nM), cobalt (0.5-6 nM), molybdenum (10-5,600 nM) and tungsten (0.3-8 nM) in Hydrate Ridge sediment porewaters. Despite low levels of cobalt and tungsten, metagenomic and metaproteomic data suggest that microbial consortia catalyzing anaerobic oxidation of methane utilize both scarce micronutrients in addition to nickel and molybdenum. Genetic machinery for cobalt-containing vitamin B12 biosynthesis was present in both anaerobic methanotrophic archaea (ANME) and sulfate-reducing bacteria (SRB). Proteins affiliated with the tungsten-containing form of formylmethanofuran dehydrogenase were expressed in ANME from two seep ecosystems, the first evidence for expression of a tungstoenzyme in psychrotolerant microorganisms. Finally, our data suggest that chemical speciation of metals in highly sulfidic porewaters may exert a stronger influence on microbial bioavailability than total concentration

  7. Geochemical, metagenomic and metaproteomic insights into trace metal utilization by methane-oxidizing microbial consortia in sulphidic marine sediments

    SciTech Connect (OSTI)

    Glass, DR. Jennifer; Yu, DR. Hang; Steele, Joshua; Dawson, Katherine; Sun, S; Chourey, Karuna; Pan, Chongle; Hettich, Robert {Bob} L; Orphan, V

    2013-01-01

    Microbes have obligate requirements for trace metals in metalloenzymes that catalyse important biogeochemical reactions. In anoxic methane- and sulphiderich environments, microbes may have unique adaptations for metal acquisition and utilization because of decreased bioavailability as a result of metal sulphide precipitation. However, micronutrient cycling is largely unexplored in cold ( 10 C) and sulphidic (> 1 mM H2S) deep-sea methane seep ecosystems. We investigated trace metal geochemistry and microbial metal utilization in methane seeps offshore Oregon and California, USA, and report dissolved concentrations of nickel (0.5 270 nM), cobalt (0.5 6 nM), molybdenum (10 5600 nM) and tungsten (0.3 8 nM) in Hydrate Ridge sediment porewaters. Despite low levels of cobalt and tungsten, metagenomic and metaproteomic data suggest that microbial consortia catalysing anaerobic oxidation of methane (AOM) utilize both scarce micronutrients in addition to nickel and molybdenum. Genetic machinery for cobalt-containing vitamin B12 biosynthesis was present in both anaerobic methanotrophic archaea (ANME) and sulphate-reducing bacteria. Proteins affiliated with the tungsten-containing form of formylmethanofuran dehydrogenase were expressed in ANME from two seep ecosystems, the first evidence for expression of a tungstoenzyme in psychrophilic microorganisms. Overall, our data suggest that AOM consortia use specialized biochemical strategies to overcome the challenges of metal availability in sulphidic environments.

  8. Solid polymer electrolyte composite membrane comprising a porous support and a solid polymer electrolyte including a dispersed reduced noble metal or noble metal oxide

    DOE Patents [OSTI]

    Liu, Han; Mittelsteadt, Cortney K; Norman, Timothy J; Griffith, Arthur E; LaConti, Anthony B

    2015-02-24

    A solid polymer electrolyte composite membrane and method of manufacturing the same. According to one embodiment, the composite membrane comprises a thin, rigid, dimensionally-stable, non-electrically-conducting support, the support having a plurality of cylindrical, straight-through pores extending perpendicularly between opposing top and bottom surfaces of the support. The pores are unevenly distributed, with some or no pores located along the periphery and more pores located centrally. The pores are completely filled with a solid polymer electrolyte, the solid polymer electrolyte including a dispersed reduced noble metal or noble metal oxide. The solid polymer electrolyte may also be deposited over the top and/or bottom surfaces of the support.

  9. Schottky barrier height reduction for holes by Fermi level depinning using metal/nickel oxide/silicon contacts

    SciTech Connect (OSTI)

    Islam, Raisul, E-mail: raisul@stanford.edu; Shine, Gautam; Saraswat, Krishna C. [Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States)

    2014-11-03

    We report the experimental demonstration of Fermi level depinning using nickel oxide (NiO) as the insulator material in metal-insulator-semiconductor (M-I-S) contacts. Using this contact, we show less than 0.1?eV barrier height for holes in platinum/NiO/silicon (Pt/NiO/p-Si) contact. Overall, the pinning factor was improved from 0.08 (metal/Si) to 0.26 (metal/NiO/Si). The experimental results show good agreement with that obtained from theoretical calculation. NiO offers high conduction band offset and low valence band offset with Si. By reducing Schottky barrier height, this contact can be used as a carrier selective contact allowing hole transport but blocking electron transport, which is important for high efficiency in photonic applications such as photovoltaics and optical detectors.

  10. Kinetics and mechanism of the outer-sphere oxidation of metal carbonyl anions with coordination complexes containing chloride

    SciTech Connect (OSTI)

    Lai, C.K.; Corraine, M.S.; Atwood, J.D.

    1992-02-01

    Reactions of metal carbonyl anions, CpFe(CO){sub 2}{sup -}, Re(CO){sub 5}{sup -}, Mn(CO){sub 5}{sup -}, CpMo(CO){sub 3}{sup -}, CpCr(CO){sub 3}{sup -}, and Co(CO){sub 4}{sup -}, with CrCl{sub 3}{center_dot}3S (S = THF, CH{sub 3}CN) and reactions of Mn(CO){sub 5}{sup -} and Re(CO){sub 5}{sup -} with [Co(o-phen){sub 2}Cl{sub 2}]CIO{sub 4} are reported. Net oxidation/reduction chemistry is observed with formation of metal carbonyl dimers and CrCl{sub 2}{center_dot}4S or Co(o-phen){sub 2}Cl{sub 2}. Metal carbonyl halides are also observed and shown to arise from a secondary reaction of the metal carbonyl dimer with the oxidant. The products and rates are most consistent with outer-sphere electron-transfer reactions. Reactions of CpFe(CO){sub 2}{sup -} with CpFe(CO){sub 2}X (X = Cl, Br, I) are also reported. The rate dependence on X is very small and in the order expected for nucleophilic substitution. 21 refs. 1 fig., 4 tabs.

  11. Simulating Valence-to-Core X-ray Emission Spectroscopy of Transition Metal Complexes with Time-Dependent Density Functional Theory

    SciTech Connect (OSTI)

    Zhang, Yu; Mukamel, Shaul; Khalil, Munira; Govind, Niranjan

    2015-11-09

    Valence-to-core (VtC) X-ray emission spectroscopy (XES) has emerged as a power- ful technique for the structural characterization of complex organometallic compounds in realistic environments. Since the spectrum represents electronic transitions from the ligand molecular orbitals to the core holes of the metal centers, the approach is more chemically sensitive to the metal-ligand bonding character compared with con- ventional X-ray absorption techniques. In this paper we study how linear-response time-dependent density functional theory (LR-TDDFT) can be harnessed to simulate K-edge VtC X-ray emission spectra reliably. LR-TDDFT allows one to go beyond the single-particle picture that has been extensively used to simulate VtC-XES. We con- sider seven low- and high-spin model complexes involving chromium, manganese and iron transition metal centers. Our results are in good agreement with experiment.

  12. Validation of MCNP6.1 for Criticality Safety of Pu-Metal, -Solution, and -Oxide Systems

    SciTech Connect (OSTI)

    Kiedrowski, Brian C.; Conlin, Jeremy Lloyd; Favorite, Jeffrey A.; Kahler, III, Albert C.; Kersting, Alyssa R.; Parsons, Donald K.; Walker, Jessie L.

    2014-05-13

    Guidance is offered to the Los Alamos National Laboratory Nuclear Criticality Safety division towards developing an Upper Subcritical Limit (USL) for MCNP6.1 calculations with ENDF/B-VII.1 nuclear data for three classes of problems: Pu-metal, -solution, and -oxide systems. A benchmark suite containing 1,086 benchmarks is prepared, and a sensitivity/uncertainty (S/U) method with a generalized linear least squares (GLLS) data adjustment is used to reject outliers, bringing the total to 959 usable benchmarks. For each class of problem, S/U methods are used to select relevant experimental benchmarks, and the calculational margin is computed using extreme value theory. A portion of the margin of sub criticality is defined considering both a detection limit for errors in codes and data and uncertainty/variability in the nuclear data library. The latter employs S/U methods with a GLLS data adjustment to find representative nuclear data covariances constrained by integral experiments, which are then used to compute uncertainties in keff from nuclear data. The USLs for the classes of problems are as follows: Pu metal, 0.980; Pu solutions, 0.973; dry Pu oxides, 0.978; dilute Pu oxide-water mixes, 0.970; and intermediate-spectrum Pu oxide-water mixes, 0.953.

  13. Method of depositing an electrically conductive oxide film on a textured metallic substrate and articles formed therefrom

    DOE Patents [OSTI]

    Christen, David K. (Oak Ridge, TN); He, Qing (Bloomington, MN)

    2001-01-01

    The present invention provides a biaxially textured laminate article having a polycrystalline biaxially textured metallic substrate with an electrically conductive oxide layer epitaxially deposited thereon and methods for producing same. In one embodiment a biaxially texture Ni substrate has a layer of LaNiO.sub.3 deposited thereon. An initial layer of electrically conductive oxide buffer is epitaxially deposited using a sputtering technique using a sputtering gas which is an inert or forming gas. A subsequent layer of an electrically conductive oxide layer is then epitaxially deposited onto the initial layer using a sputtering gas comprising oxygen. The present invention will enable the formation of biaxially textured devices which include HTS wires and interconnects, large area or long length ferromagnetic and/or ferroelectric memory devices, large area or long length, flexible light emitting semiconductors, ferroelectric tapes, and electrodes.

  14. Method of depositing an electrically conductive oxide film on a textured metallic substrate and articles formed therefrom

    DOE Patents [OSTI]

    Christen, David K. (Oak Ridge, TN); He, Qing (Bloomington, MN)

    2003-04-29

    The present invention provides a biaxially textured laminate article having a polycrystalline biaxially textured metallic substrate with an electrically conductive oxide layer epitaxially deposited thereon and methods for producing same. In one embodiment a biaxially texture Ni substrate has a layer of LaNiO.sub.3 deposited thereon. An initial layer of electrically conductive oxide buffer is epitaxially deposited using a sputtering technique using a sputtering gas which is an inert or forming gas. A subsequent layer of an electrically conductive oxide layer is then epitaxially deposited onto the initial layer using a sputtering gas comprising oxygen. The present invention will enable the formation of biaxially textured devices which include HTS wires and interconnects, large area or long length ferromagnetic and/or ferroelectric memory devices, large area or long length, flexible light emitting semiconductors, ferroelectric tapes, and electrodes.

  15. Support shape effect in metal oxide catalysis: ceria nanoshapes supported vanadia catalysts for oxidative dehydrogenation of iso-butane

    SciTech Connect (OSTI)

    Wu, Zili; Schwartz, Viviane; Li, Meijun; Rondinone, Adam Justin; Overbury, Steven {Steve} H

    2012-01-01

    The activation energy of VOx/CeO2 catalysts in oxidative dehydrogenation of iso-butane was found dependent on the shape of ceria support: rods < octahedra, closely related to the surface oxygen vacancy formation energy and defects amount of the two ceria supports with different crystallographic surface planes.

  16. Trending: Metal Oxo Bonds

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Trending: Metal Oxo Bonds Trending: Metal Oxo Bonds Print Wednesday, 29 May 2013 00:00 Metal oxides are important for scientific and technical applications in a variety of disciplines, including materials science, chemistry, and biology. Highly covalent metal-oxygen multiple bonds (metal oxos) are the building blocks of metal oxides and have a bearing on the oxide's desirable chemical, magnetic, electronic, and thermal properties. The lack of a more sophisticated grasp of bonding in metal oxides

  17. Doped palladium containing oxidation catalysts

    DOE Patents [OSTI]

    Mohajeri, Nahid

    2014-02-18

    A supported oxidation catalyst includes a support having a metal oxide or metal salt, and mixed metal particles thereon. The mixed metal particles include first particles including a palladium compound, and second particles including a precious metal group (PMG) metal or PMG metal compound, wherein the PMG metal is not palladium. The oxidation catalyst may also be used as a gas sensor.

  18. High Activity of Ce1-xNixO2-y for H2 Production through Ethanol Steam Reforming: Tuning Catalytic Performance through Metal-Oxide Interactions

    SciTech Connect (OSTI)

    G Zhou; L Barrio; S Agnoli; S Senanayake; J Evans; A Kubacka; M Estrella; J Hanson; A Martinez-Arias; et al.

    2011-12-31

    The importance of the oxide: Ce{sub 0.8}Ni{sub 0.2}O{sub 2-y} is an excellent catalyst for ethanol steam reforming. Metal-oxide interactions perturb the electronic properties of the small particles of metallic nickel present in the catalyst under the reaction conditions and thus suppress any methanation activity. The nickel embedded in ceria induces the formation of O vacancies, which facilitate cleavage of the OH bonds in ethanol and water.

  19. A 1 A laser driver in 0.35 {mu}m complementary metal oxide semiconductor technology for a pulsed time-of-flight laser rangefinder

    SciTech Connect (OSTI)

    Nissinen, Jan; Kostamovaara, Juha

    2009-10-15

    An integrated complementary metal oxide semiconductor (CMOS) current pulse generator is presented which achieves an ampere-scale peak current pulse with a rise time and pulse width of less than 1 and 2.5 ns (pulse width at half maximum), respectively. The generator is implemented in a 0.35 {mu}m CMOS process and consists of four parallel n-type metal oxide semiconductor transistors driven by a scaled buffer chain to achieve fast switching.

  20. Assessing the density functional theory-based multireference configuration interaction (DFT/MRCI) method for transition metal complexes

    SciTech Connect (OSTI)

    Escudero, Daniel E-mail: thiel@kofo.mpg.de; Thiel, Walter E-mail: thiel@kofo.mpg.de

    2014-05-21

    We report an assessment of the performance of density functional theory-based multireference configuration interaction (DFT/MRCI) calculations for a set of 3d- and 4d-transition metal (TM) complexes. The DFT/MRCI results are compared to published reference data from reliable high-level multi-configurational ab initio studies. The assessment covers the relative energies of different ground-state minima of the highly correlated CrF{sub 6} complex, the singlet and triplet electronically excited states of seven typical TM complexes (MnO{sub 4}{sup ?}, Cr(CO){sub 6}, [Fe(CN){sub 6}]{sup 4?}, four larger Fe and Ru complexes), and the corresponding electronic spectra (vertical excitation energies and oscillator strengths). It includes comparisons with results from different flavors of time-dependent DFT (TD-DFT) calculations using pure, hybrid, and long-range corrected functionals. The DFT/MRCI method is found to be superior to the tested TD-DFT approaches and is thus recommended for exploring the excited-state properties of TM complexes.