National Library of Energy BETA

Sample records for transition metal oxide

  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. Pressure-Induced Electronic Phase Transitions Transition Metal Oxides and Rare Earth Metals

    E-Print Network [OSTI]

    Islam, M. Saif

    Pressure-Induced Electronic Phase Transitions in Transition Metal Oxides and Rare Earth Metals Metal Oxides and Rare Earth Metals by Brian Ross Maddox Electron correlation can affect profound changes transition in a transition metal monoxide. iv #12;The lanthanides (the 4f metals also known as rare-earths

  3. Synthesis and characterization of nanostructured transition metal oxides for energy storage devices

    E-Print Network [OSTI]

    Kim, Jong Woung

    2012-01-01

    nanostructured transition metal oxides for energy storage devicesnanostructured transition metal oxides for energy storage devices

  4. Transition metal oxide improves overall efficiency and maintains performance with inexpensive metals.

    E-Print Network [OSTI]

    that inserting a transition metal oxide (TMO) between the lead sulfide (PbS) quantum dot (QD) layer and the metalTransition metal oxide improves overall efficiency and maintains performance with inexpensive of performance. n-type TMOs consisting of molybdenum oxide (MoOx) and vanadium oxide (V2Ox) were used

  5. Charge, orbital and magnetic ordering in transition metal oxides 

    E-Print Network [OSTI]

    Senn, Mark Stephen

    2013-06-29

    Neutron and x-ray diffraction has been used to study charge, orbital and magnetic ordering in some transition metal oxides. The long standing controversy regarding the nature of the ground state (Verwey structure) of the ...

  6. High-Pressure Thermodynamic Properties of f-electron Metals, Transition Metal Oxides, and Half-Metallic Magnets

    SciTech Connect (OSTI)

    Richard T. Scalettar; Warren E. Pickett

    2005-08-02

    This project involves research into the thermodynamic properties of f-electron metals, transition metal oxides, and half-metallic magnets at high pressure. These materials are ones in which the changing importance of electron-electron interactions as the distance between atoms is varied can tune the system through phase transitions from localized to delocalized electrons, from screened to unscreened magnetic moments, and from normal metal to one in which only a single spin specie can conduct. Three main thrusts are being pursued: (i) Mott transitions in transition metal oxides, (ii) magnetism in half-metallic compounds, and (iii) large volume-collapse transitions in f-band metals.

  7. Resonant Ultrasound Studies of Complex Transition Metal Oxides

    SciTech Connect (OSTI)

    Dr. Henry Bass; Dr. J. R. Gladden

    2008-08-18

    Department of Energy EPSCoR The University of Mississippi Award: DE-FG02-04ER46121 Resonant Ultrasound Spectroscopy Studies of Complex Transition Metal Oxides The central thrust of this DOE funded research program has been to apply resonant ultrasound spectroscopy (RUS), an elegant and efficient method for determining the elastic stiffness constants of a crystal, to the complex and poorly understood class of materials known as transition metal oxides (TMOs). Perhaps the most interesting and challenging feature of TMOs is their strongly correlated behavior in which spin, lattice, and charge degrees of freedom are strongly coupled. Elastic constants are a measure of the interatomic potentials in a crystal and are thus sensitive probes into the atomic environment. This sensitivity makes RUS an ideal tool to study the coupling of phase transition order parameters to lattice strains. The most significant result of the project has been the construction of a high temperature RUS apparatus capable of making elastic constant measurements at temperatures as high as 1000 degrees Celsius. We have designed and built novel acoustic transducers which can operate as high as 600 degrees Celsius based on lithium niobate piezoelectric elements. For measurement between 600 to 1000 C, a buffer rod system is used in which the samples under test and transducers are separated by a rod with low acoustic attenuation. The high temperature RUS system has been used to study the charge order (CO) transition in transition metal oxides for which we have discovered a new transition occurring about 35 C below the CO transition. While the CO transition exhibits a linear coupling between the strain and order parameter, this new precursor transition shows a different coupling indicating a fundamentally different mechanism. We have also begun a study, in collaboration with the Jet Propulsion Laboratory, to study novel thermoelectric materials at elevated temperatures. These materials include silicon germanium with various doping and Zintl phase materials. Such materials show promise for increased figures of merit, vital to making thermolectrics competitive with traditional power generation mechanisms.

  8. Methane-to-Methanol Conversion by Gas-Phase Transition Metal Oxide Cations: Experiment and Theory

    E-Print Network [OSTI]

    Metz, Ricardo B.

    Methane-to-Methanol Conversion by Gas-Phase Transition Metal Oxide Cations: Experiment and Theory-phase transition metal oxide cations can convert methane to methanol. Methane activation by MO+ is discussed reaction are also presented. Introduction The direct oxidation of methane to an easily transportable liquid

  9. Electrochemical lithiation and delithiation for control of magnetic properties of nanoscale transition metal oxides

    E-Print Network [OSTI]

    Sivakumar, Vikram

    2008-01-01

    Transition metal oxides comprise a fascinating class of materials displaying a variety of magnetic and electronic properties, ranging from half-metallic ferromagnets like CrO2, ferrimagnetic semiconductors like Fey's, and ...

  10. 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.

  11. Oxidative dehydrogenation (ODH) of ethane with O2 as oxidant on selected transition metal-loaded zeolites

    E-Print Network [OSTI]

    Poeppelmeier, Kenneth R.

    Oxidative dehydrogenation (ODH) of ethane with O2 as oxidant on selected transition metal Accepted 14 April 2009 Available online 17 May 2009 Keywords: Oxidative dehydrogenation Ethane Ethylene of ethane (ODHE) to ethylene were characterized. Acidic Ni-loaded Y zeolite exhibits an ethylene

  12. Theory of nitride oxide adsorption on transition metal (111) surfaces: a first-principles investigation

    E-Print Network [OSTI]

    Li, Weixue

    In this work, we report a density functional theory study of nitric oxide (NO) adsorption on close of NO adsorption on TM(111) surfaces in the submonolayer regime. 1. Introduction The catalytic reduction of NOxTheory of nitride oxide adsorption on transition metal (111) surfaces: a first

  13. 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.

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

    Office of Scientific and Technical Information (OSTI)

    for Tunable THz Plasmonic Metamaterials The outline of this presentation are: (1) Motivation - Non-tunability of metal metamaterials; (2) Superconductors for temperature tunable...

  15. Spin and orbital ordering in ternary transition metal oxides 

    E-Print Network [OSTI]

    Kimber, Simon A. J.

    Spin and orbital orderings are amongst the most important phenomena in the solid state chemistry of oxides. Physical property and powder neutron and X-ray diffraction measurements are reported for a range of mostly low ...

  16. 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.

  17. 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.

  18. Synthesis and characterization of nanostructured transition metal oxides for energy storage devices

    E-Print Network [OSTI]

    Kim, Jong Woung

    2012-01-01

    Figure 1.1. Ragone plot of various energy storage systems [metal oxides for energy storage devices A dissertationmetal oxides for energy storage devices by Jong Woung Kim

  19. 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}.

  20. Finding Room for Improvement in Transition Metal Oxides Cathodes for Lithium-ion Batteries

    E-Print Network [OSTI]

    Kam, Kinson

    2012-01-01

    Metal Oxides Cathodes for Lithium-ion Batteries Kinson C.storage using rechargeable lithium-ion batteries has become

  1. Electrical conductivity in oxygen-deficient phases of transition metal oxides from first-principles calculations.

    SciTech Connect (OSTI)

    Bondi, Robert James; Desjarlais, Michael Paul; Thompson, Aidan Patrick; Brennecka, Geoffrey L.; Marinella, Matthew

    2013-09-01

    Density-functional theory calculations, ab-initio molecular dynamics, and the Kubo-Greenwood formula are applied to predict electrical conductivity in Ta2Ox (0x5) as a function of composition, phase, and temperature, where additional focus is given to various oxidation states of the O monovacancy (VOn; n=0,1+,2+). Our calculations of DC conductivity at 300K agree well with experimental measurements taken on Ta2Ox thin films and bulk Ta2O5 powder-sintered pellets, although simulation accuracy can be improved for the most insulating, stoichiometric compositions. Our conductivity calculations and further interrogation of the O-deficient Ta2O5 electronic structure provide further theoretical basis to substantiate VO0 as a donor dopant in Ta2O5 and other metal oxides. Furthermore, this dopant-like behavior appears specific to neutral VO cases in both Ta2O5 and TiO2 and was not observed in other oxidation states. This suggests that reduction and oxidation reactions may effectively act as donor activation and deactivation mechanisms, respectively, for VO0 in transition metal oxides.

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

    SciTech Connect (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.

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

    SciTech Connect (OSTI)

    Venkatesh, Koppampatti R.; Hu, Jianli; Tierney, John W.; Wender, Irving

    1996-12-01

    A method is described for 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 and 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.

  4. Methane Activation by Transition-Metal Oxides, MOx (M ) Cr, Mo, W; x ) 1, 2, 3) Xin Xu,# Francesco Faglioni, and William A. Goddard, III*

    E-Print Network [OSTI]

    Goddard III, William A.

    Methane Activation by Transition-Metal Oxides, MOx (M ) Cr, Mo, W; x ) 1, 2, 3) Xin Xu,# Francesco, 2002 Recent experiments on the dehydrogenation-aromatization of methane (DHAM) to form benzene using a MoO3/HZSM-5 catalyst stimulated us to examine methane activation by the transition-metal oxide

  5. Single-step preparation and consolidation of reduced early-transition-metal oxide/metal n-type thermoelectric composites

    E-Print Network [OSTI]

    Gaultois, Michael W; Douglas, Jason E; Sparks, Taylor D; Seshadri, Ram

    2015-01-01

    oxide/metal n-type thermoelectric composites Michael W.here as interesting thermoelectric materials. Numerous2.5 W m ?1 K ?1 . Thermoelectric properties of these n-type

  6. Improved layered mixed transition metal oxides for Li-ion batteries

    SciTech Connect (OSTI)

    Doeff, Marca M.; Conry, Thomas; Wilcox, James

    2010-03-05

    Recent work in our laboratory has been directed towards development of mixed layered transition metal oxides with general composition Li[Ni, Co, M, Mn]O2 (M=Al, Ti) for Li ion battery cathodes. Compounds such as Li[Ni1/3Co1/3Mn1/3]O2 (often called NMCs) are currently being commercialized for use in consumer electronic batteries, but the high cobalt content makes them too expensive for vehicular applications such as electric vehicles (EV), plug-in hybrid electric vehicles (PHEVs), or hybrid electric vehicles (HEVs). To reduce materials costs, we have explored partial or full substitution of Co with Al, Ti, and Fe. Fe substitution generally decreases capacity and results in poorer rate and cycling behavior. Interestingly, low levels of substitution with Al or Ti improve aspects of performance with minimal impact on energy densities, for some formulations. High levels of Al substitution compromise specific capacity, however, so further improvements require that the Ni and Mn content be increased and Co correspondingly decreased. Low levels of Al or Ti substitution can then be used offset negative effects induced by the higher Ni content. The structural and electrochemical characterization of substituted NMCs is presented in this paper.

  7. 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.

  8. Laser Desorption/Ionization of Transition Metal Atoms and Oxides from Solid Argon Lester Andrews,*, Andreas Rohrbacher, Christopher M. Laperle, and Robert E. Continetti

    E-Print Network [OSTI]

    Continetti, Robert E.

    Laser Desorption/Ionization of Transition Metal Atoms and Oxides from Solid Argon Lester Andrews of the laser-ablated metal atoms and O2 in excess argon during condensation at 10 K, have been laser desorbed of organic acid typically used as a matrix in matrix- assisted laser desorption/ionization (MALDI) mass

  9. 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.

  10. 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.

  11. 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.

  12. Fluorescence-based detection methodologies for nitric oxide using transition metal scaffolds

    E-Print Network [OSTI]

    Hilderbrand, Scott A. (Scott Alan), 1976-

    2004-01-01

    Chapter 1. Fluorescence-Based Detection Methodologies for Nitric Oxide: A Review. Chapter 2. Cobalt Chemistry with Mixed Aminotroponimine Salicylaldimine Ligands: Synthesis, Characterization, and Nitric Oxide Reactivity. ...

  13. Finding Room for Improvement in Transition Metal Oxides Cathodes for Lithium-ion Batteries

    E-Print Network [OSTI]

    Kam, Kinson

    2012-01-01

    Oxides Cathodes for Lithium-ion Batteries Kinson C. Kam andusing rechargeable lithium-ion batteries has become an

  14. Highly stable and high power efficiency tandem organic light-emitting diodes with transition metal oxide-based charge generation layers

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    efficiency improvement Transition metal oxide a b s t r a c t Tandem organic light-emitting diodes (OLEDs. Ó 2015 Elsevier B.V. All rights reserved. 1. Introduction Organic light-emitting diodes (OLEDs) [1 displays and lighting panels. However, before mass production of OLEDs for the consumer market can start

  15. The detection of nitric oxide and its reactivity with transition metal thiolate complexes

    E-Print Network [OSTI]

    Tennyson, Andrew Gregory

    2008-01-01

    Nitric oxide (NO) is a molecule that is essential for life and regulates both beneficial and harmful processes. Because this gaseous radical influences many aspects of health and disease, we wish to explore the relationship ...

  16. Mechanism of oxygen reduction reaction on transition metal oxide catalysts for high temperature fuel cells

    E-Print Network [OSTI]

    La O', Gerardo Jose Cordova

    2008-01-01

    The solid oxide fuel cell (SOFC) with its high energy conversion efficiency, low emissions, silent operation and its ability to utilize commercial fuels has the potential to create a large impact on the energy landscape. ...

  17. Ab initio screening of lithium diffusion rates in transition metal oxide cathodes for lithium ion batteries

    E-Print Network [OSTI]

    Moore, Charles J. (Charles Jacob)

    2012-01-01

    A screening metric for diffusion limitations in lithium ion battery cathodes is derived using transition state theory and common materials properties. The metric relies on net activation barrier for lithium diffusion. ...

  18. Interplay between electronic structure and catalytic activity in transition metal oxide model system

    E-Print Network [OSTI]

    Suntivich, Jin

    2012-01-01

    The efficiency of many energy storage and conversion technologies, such as hydrogen fuel cells, rechargeable metal-air batteries, and hydrogen production from water splitting, is limited by the slow kinetics of the oxygen ...

  19. The design of new ligands and transition metal compounds for the oxidation of organic compounds 

    E-Print Network [OSTI]

    Grill, Joseph Michael

    2009-06-02

    A review of metal-mediated epoxidation is given. Jacobsen's catalyst and the Sharpless asymmetric epoxidation catalyst are discussed. The origins of enantioselectivity are explained using stereochemical models. Several new ...

  20. 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.

  1. 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

  2. Transition Metal Switchable Mirror

    SciTech Connect (OSTI)

    2009-08-21

    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.

  3. Transition Metal Switchable Mirror

    SciTech Connect (OSTI)

    None

    2009-01-01

    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

  4. Oxidation energies of transition metal oxides within the GGA+U framework Lei Wang, Thomas Maxisch, and Gerbrand Ceder*

    E-Print Network [OSTI]

    Ceder, Gerbrand

    is computed using the generalized gradient approach GGA and GGA+U methods. Two substantial contributions, combustion, metal refining, electrochemical energy generation and storage, photosynthesis, and metabolism and generalized gradient approxima- tion GGA , two standard approximations to density func- tional theory DFT

  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. 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.

  7. Extracting metals directly from metal oxides

    DOE Patents [OSTI]

    Wai, Chien M. (Moscow, ID); Smart, Neil G. (Moscow, ID); Phelps, Cindy (Moscow, ID)

    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.

  8. 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.

  9. Versatile Applications of Nanostructured Metal Oxides

    E-Print Network [OSTI]

    Li, Li

    2014-05-29

    of nanopar- ticles becomes broader, an onion type morphology was observed, particles larger than RPEO segregate out, forming a silica-rich core surrounded by a lamellar or lamel- lar/hexagonal structure. This can be understood by the entropic contributions... , acids or bases, metal salts, enzymes, radical initia- tors and solvents. Heterogeneous catalysts typically are solids that do not dissolve. For example, supported metals, transition metal oxides and sulfides, solid acids and bases, immobilized enzymes...

  10. 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.

  11. 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.

  12. 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.

  13. Magnetic Properties of Mesoporous and Nano-particulate Metal Oxides 

    E-Print Network [OSTI]

    Hill, Adrian H

    2009-01-01

    The magnetic properties of the first row transition metal oxides are wide and varied and have been studied extensively since the 1930’s. Observations that the magnetic properties of these material types change with the ...

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. Electrochemistry, Photoelectrochemistry And Photoelectron Spectroscopy Of Nanostructured Metal Oxides

    E-Print Network [OSTI]

    Södergren, S

    1997-01-01

    Electrochemistry, Photoelectrochemistry And Photoelectron Spectroscopy Of Nanostructured Metal Oxides

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. Catalysis by Confinement: Enthalpic Stabilization of NO Oxidation Transition States by Micropororous and Mesoporous Siliceous

    E-Print Network [OSTI]

    Iglesia, Enrique

    . INTRODUCTION The homogeneous oxidation of nitric oxide (NO) to nitrogen dioxide (NO2) with O2 as the oxidant transformation in selective catalytic NOx reduction (SCR) by NH3 on metal- exchanged zeolites7-11 and in NOxCatalysis by Confinement: Enthalpic Stabilization of NO Oxidation Transition States

  8. 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.

  9. 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.

  10. Metal complexes of substituted Gable porphyrins as oxidation catalysts

    DOE Patents [OSTI]

    Lyons, James E. (Wallingford, PA); Ellis, Jr., Paul E. (Downingtown, PA); Wagner, Richard W. (Murrysville, PA)

    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.

  11. 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.

  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. 9 Metal to Non-metal Transitions in Solids and on Surfaces studied using Photoemission Spectroscopy

    E-Print Network [OSTI]

    Redner, Sidney

    9 Metal to Non-metal Transitions in Solids and on Surfaces studied using Photoemission Spectroscopy of the electrical properties of a material between those of a metal and those of a non-metal (be it semiconducting metal to non-metal transitions. (Thephrase `metal to non-metal transition' is used in this paper

  14. 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.

  15. 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.

  16. 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.

  17. Transition metal fluorides: from superconductors to multiferroics. 

    E-Print Network [OSTI]

    Drathen, Christina

    2013-06-29

    Transition metal fluorides represent an important family of complex solids displaying a variety of different properties and interesting phenomena. Despite their remarkable behaviour, these classes of materials have not ...

  18. 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.

  19. Three-Electrode Metal Oxide Reduction Cell

    DOE Patents [OSTI]

    Dees, Dennis W. (Downers Grove, IL); Ackerman, John P. (Downers Grove, IL)

    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.

  20. Three-electrode metal oxide reduction cell

    DOE Patents [OSTI]

    Dees, Dennis W. (Downers Groves, IL); Ackerman, John P. (Downers Grove, IL)

    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.

  1. Method for making monolithic metal oxide aerogels

    SciTech Connect (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.

  2. 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.

  3. Direct electrochemical reduction of metal-oxides

    DOE Patents [OSTI]

    Redey, Laszlo I. (Downers Grove, IL); Gourishankar, Karthick (Downers Grove, IL)

    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.

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

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

    Search Title: Microbial-mediated method for metal oxide nanoparticle formation The invention is directed to a method for producing metal oxide nanoparticles, the method...

  5. Nanocomposite of graphene and metal oxide materials | OSTI, US...

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

    Nanocomposite of graphene and metal oxide materials Re-direct Destination: Nanocomposite materials comprising a metal oxide bonded to at least one graphene material. The...

  6. 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...

  7. Metal Oxide Semiconductor Nanoparticles Open the Door to New...

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

    Metal Oxide Semiconductor Nanoparticles Open the Door to New Medical Innovations Technology available for licensing: novel nanometer-sized metal oxide semiconductors that allow...

  8. 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.

  9. 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.

  10. 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.

  11. [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.

  12. 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.

  13. 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.

  14. 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.

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

    DOE Patents [OSTI]

    Wijesekera, Tilak (Glen Mills, PA); Lyons, James E. (Wallingford, PA); Ellis, Jr., Paul E. (Downingtown, PA); Bhinde, Manoj V. (Boothwyn, PA)

    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.

  16. Method for making monolithic metal oxide aerogels

    SciTech Connect (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.

  17. 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.

  18. PLUTONIUM METAL: OXIDATION CONSIDERATIONS AND APPROACH

    SciTech Connect (OSTI)

    Estochen, E.

    2013-03-20

    Plutonium is arguably the most unique of all metals when considered in the combined context of metallurgical, chemical, and nuclear behavior. Much of the research in understanding behavior and characteristics of plutonium materials has its genesis in work associated with nuclear weapons systems. However, with the advent of applications in fuel materials, the focus in plutonium science has been more towards nuclear fuel applications, as well as long term storage and disposition. The focus of discussion included herein is related to preparing plutonium materials to meet goals consistent with non-proliferation. More specifically, the emphasis is on the treatment of legacy plutonium, in primarily metallic form, and safe handling, packaging, and transport to meet non-proliferation goals of safe/secure storage. Elevated temperature oxidation of plutonium metal is the treatment of choice, due to extensive experiential data related to the method, as the oxide form of plutonium is one of only a few compounds that is relatively simple to produce, and stable over a large temperature range. Despite the simplicity of the steps required to oxidize plutonium metal, it is important to understand the behavior of plutonium to ensure that oxidation is conducted in a safe and effective manner. It is important to understand the effect of changes in environmental variables on the oxidation characteristics of plutonium. The primary purpose of this report is to present a brief summary of information related to plutonium metal attributes, behavior, methods for conversion to oxide, and the ancillary considerations related to processing and facility safety. The information provided is based on data available in the public domain and from experience in oxidation of such materials at various facilities in the United States. The report is provided as a general reference for implementation of a simple and safe plutonium metal oxidation technique.

  19. Thermodynamic Investigations of Lithium- and Manganese-Rich Transition...

    Office of Environmental Management (EM)

    Thermodynamic Investigations of Lithium- and Manganese-Rich Transition Metal Oxides Thermodynamic Investigations of Lithium- and Manganese-Rich Transition Metal Oxides 2013 DOE...

  20. 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...

  1. Selective Catalytic Oxidation (SCO) of NH3 to N2 for Hot Exhaust Treatment

    Broader source: Energy.gov [DOE]

    Investigation of a series of transition metal oxides and precious metal based catalysts for ammonia selective oxidation at low temperatures

  2. 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.

  3. 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.

  4. 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.

  5. Spectroscopic studies of metal growth on oxides 

    E-Print Network [OSTI]

    Luo, Kai

    2000-01-01

    of metal clusters on well-defined oxide surfaces. In this work, the nucleation and growth modes of Ag on TiO?(110)(1x1) and (1x2) surfaces, Ag on ultra-thin Al?O? films, and Au on ultra-thin SiO? films were studied by scanning tunneling microscopy (STM...

  6. Metal-insulator transition in holography

    E-Print Network [OSTI]

    Aristomenis Donos; Sean A. Hartnoll

    2013-01-19

    We exhibit an interaction-driven metal-insulator quantum phase transition in a holographic model. Use of a helical lattice enables us to break translation invariance while preserving homogeneity. The metallic phase is characterized by a sharp Drude peak and a d.c. resistivity that increases with temperature. In the insulating phase the Drude spectral weight is transferred into a `mid-infrared' peak and to energy scales of order the chemical potential. The d.c. resistivity now decreases with temperature. In the metallic phase, operators breaking translation invariance are irrelevant at low energy scales. In the insulating phase, translation symmetry breaking effects are present at low energies. We find the near horizon extremal geometry that captures the insulating physics.

  7. 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.

  8. 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.

  9. 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.

  10. "Metal-oxide gas sensors have been around for

    E-Print Network [OSTI]

    Diebold, Ulrike

    Publishing "Metal-oxide gas sensors have been around for over 40 years, but only now we have: Surface Studies of Gas Sensing Metal Oxides 21 February 2007 1. Could you explain the significance of your article to the non-specialist? Metal oxide-gas sensors are practical devices used in a variety of every

  11. Transition Metal Nutrition: A Balance Between Deficiency and Toxicity

    E-Print Network [OSTI]

    Hamel, Patrice

    333 Transition Metal Nutrition: A Balance Between Deficiency and Toxicity CHAPTER 10 CHAPTER CONTENTS I. Introduction 334 II. Components of the metal homeostasis network 335 A. Metal transporters 335 B. Metal chelation 349 C. Differences with other photosynthetic organisms 352 III. Metal tolerance

  12. 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

  13. 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.

  14. 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.

  15. 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.

  16. Semiconductor to Metal to Half-Metal Transition in Pt-Embedded Zigzag Graphene Nanoribbons

    E-Print Network [OSTI]

    Krasheninnikov, Arkady V.

    Semiconductor to Metal to Half-Metal Transition in Pt-Embedded Zigzag Graphene Nanoribbons Xiaohui properties of Pt-embedded zigzag graphene nanoribbons (Pt-ZGNRs) are investigated using density-functional theory calculations. It is found that Pt-ZGNRs exhibit a semiconductor-metal-half-metal transition

  17. 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.

  18. 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.

  19. 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.

  20. Insulator/metal phase transition and colossal magnetoresistance in holographic model

    E-Print Network [OSTI]

    Rong-Gen Cai; Run-Qiu Yang

    2015-07-27

    Within massive gravity, we construct a gravity dual for insulator/metal phase transition and colossal magnetoresistance (CMR) effect found in some manganese oxides materials. In heavy graviton limit, a remarkable magnetic-field-sensitive DC resistivity peak appears at the Curie temperature, where an insulator/metal phase transition happens and the magnetoresistance is scaled with the square of field-induced magnetization. We find that metallic and insulating phases coexist below the Curie point and the relation with the electronic phase separation is discussed.

  1. 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.

  2. Promises and problems with metallic interconnects for reduced temperature solid oxide fuel cells

    E-Print Network [OSTI]

    Hou, Peggy Y.; Huang, Keqin; Bakker, Wate T.

    1999-01-01

    METALLIC INTERCONNECTS FOR REDUCED TEMPERATURE SOLID OXIDE FUELto fuel cell stacks with multiple metallic interconnects.

  3. 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...

  4. 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...

  5. Extraction of exchange parameters in transition-metal perovskites...

    Office of Scientific and Technical Information (OSTI)

    Extraction of exchange parameters in transition-metal perovskites Citation Details In-Document Search This content will become publicly available on September 14, 2016 Title:...

  6. 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...

  7. 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 3Hsubscript 2O Citation Details In-Document Search Title:...

  8. 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,...

  9. Electronic Transitions in Perovskite Oxide Heterostructures

    E-Print Network [OSTI]

    Wong, Franklin

    2011-01-01

    alkaline-earth metals, rare-earth metals, Bi, and Pb. Withalkaline-earth and rare-earth metals occupy the A sites and3 (R = trivalent rare-earth metal, A = divalent alkaline-

  10. 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

  11. 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.

  12. 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.

  13. Use of Transition Metal Forms in Separation of Lipid Components 

    E-Print Network [OSTI]

    Kulkarni, Sayali V

    2014-08-01

    AND MATERIALS ................................................................................. 16 3.1 Evaluation of Effectives of Free Forms of Transition Metal Ions to form Complexes with Olefinic Double Bond in an Organic- Aqueous Two-Phase System... ............................................... 24 4. RESULTS AND DISCUSSION .................................................................................. 26 4.1 Evaluation of Effectives of Transition Metal Ions to form Complexes with Olefinic Double Bond in an Organic-Aqueous Two- Phase...

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

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

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

  15. Electronic Transitions in Perovskite Oxide Heterostructures

    E-Print Network [OSTI]

    Wong, Franklin

    2011-01-01

    perovskite . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21 i The distorted perovskite . . . . . . . .Basic Aspects of Correlated Perovskite Oxides The Perovskite

  16. 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.

  17. METAL-NON METAL TRANSITIONS /N RARE EARTH COMPOUNDS. EXPERIMENT AND THEORK /.

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    METAL-NON METAL TRANSITIONS /N RARE EARTH COMPOUNDS. EXPERIMENT AND THEORK /. VALENCE INSTABILITIES, superconductivity, electron-phonon and band theory, to name a few. 2. Properties of normal rare earth metals. - Before discussing rare earth valence instabilities, three relevant general features of rare earth metals

  18. 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.

  19. 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.

  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. 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

  2. Metal oxide/organic interface investigations for photovoltaic devices

    E-Print Network [OSTI]

    Pachoumi, Olympia

    2014-10-07

    the performance and stability of interfacial charge extraction layers for organic solar cells. Two novel ternary metal oxides, zinc-strontrium- oxide (ZnSrO) and zinc-barium-oxide (ZnBaO), were fabricated and their use as electron extraction layers in inverted...

  3. 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.

  4. 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.

  5. Nitrene transfer reactions by late transition metal complexes

    E-Print Network [OSTI]

    Hamilton, Charles W., Ph. D. Massachusetts Institute of Technology

    2007-01-01

    This thesis presents nitrene transfer reactions that are catalyzed or mediated by late transition metal complexes. Sterically large, fluorinated supporting ligands are used to minimize potential side reactions. A new ...

  6. Optical properties of two-dimensional transition metal dichalcogenides

    E-Print Network [OSTI]

    Lin, Yuxuan, S.M. Massachusetts Institute of Technology

    2014-01-01

    The re-discovery of the atomically thin transition metal dichalcogenides (TMDs), which are mostly semiconductors with a wide range of band gaps, has diversified the family of two-dimensional materials and boosted the ...

  7. Photochemical reductive elimination of halogen from transition metal complexes

    E-Print Network [OSTI]

    Cook, Timothy R. (Timothy Raymond), 1982-

    2010-01-01

    This thesis is focused on the synthesis and study of transition metal complexes that undergo halogen elimination when irradiated with UV and visible light. This chemistry is relevant for solar energy storage schemes in ...

  8. Formation of metal oxides by cathodic arc deposition

    SciTech Connect (OSTI)

    Anders, S.; Anders, A.; Rubin, M.; Wang, Z.; Raoux, S.; Kong, F.; Brown, I.G.

    1995-03-01

    Metal oxide thin films are of interest for a number of applications. Cathodic arc deposition, an established, industrially applied technique for formation of nitrides (e.g. TiN), can also be used for metal oxide thin film formation. A cathodic arc plasma source with desired cathode material is operated in an oxygen atmosphere, and metal oxides of various stoichiometric composition can be formed on different substrates. We report here on a series of experiments on metal oxide formation by cathodic arc deposition for different applications. Black copper oxide has been deposited on ALS components to increase the radiative heat transfer between the parts. Various metal oxides such as tungsten oxide, niobium oxide, nickel oxide and vanadium oxide have been deposited on ITO glass to form electrochromic films for window applications. Tantalum oxide films are of interest for replacing polymer electrolytes. Optical waveguide structures can be formed by refractive index variation using oxide multilayers. We have synthesized multilayers of Al{sub 2}O{sub 3}/Y{sub 2}O{sub 3}/AI{sub 2}O{sub 3}/Si as possible basic structures for passive optoelectronic integrated circuits, and Al{sub 2-x}Er{sub x}O{sub 3} thin films with a variable Er concentration which is a potential component layer for the production of active optoelectronic integrated devices such as amplifiers or lasers at a wavelength of 1.53 {mu}m. Aluminum and chromium oxide films have been deposited on a number of substrates to impart improved corrosion resistance at high temperature. Titanium sub-oxides which are electrically conductive and corrosion resistant and stable in a number of aggressive environments have been deposited on various substrates. These sub-oxides are of great interest for use in electrochemical cells.

  9. Solution-mediated strategies for synthesizing metal oxides, borates and phosphides using nanocrystals as reactive precursors 

    E-Print Network [OSTI]

    Henkes, Amanda Erin

    2009-05-15

    ) the solution-mediated diffusion of phosphorus into a nanocrystalline metal to form target metal phosphides. To form multi-metal oxides using the first strategy, metal oxide nanoparticle precursors are mixed in stoichiometric ratios in solution to form a...

  10. 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.

  11. 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.

  12. 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.

  13. Metal - non-metal transition and the second critical point in expanded metals

    E-Print Network [OSTI]

    V. B. Bobrov; S. A. Trigger; A. G. Zagorodny

    2013-02-16

    Based on the non-relativistic Coulomb model within which the matter is a system of interacting electrons and nuclei, using the quantum field theory and linear response theory methods, opportunity for the existence of the second critical point in expanded metals, which is directly related to the metal--nonmetal transition, predicted by Landau and Zeldovitch, is theoretically justified. It is shown that the matter at the second critical point is in the state of true dielectric with zero static conductivity. The results obtained are in agreement with recent experiments for expanded metals. The existence of the second critical point is caused by the initial multi-component nature of the matter consisting of electrons and nuclei and the long-range character of the Coulomb interaction. (Accepted in PTEP)

  14. Metal Oxide Thin Films Deposited from Metal Organic Precursors in Supercritical CO2 Solutions

    E-Print Network [OSTI]

    Gougousi, Theodosia

    Metal Oxide Thin Films Deposited from Metal Organic Precursors in Supercritical CO2 Solutions and oxidizing agents are delivered in liquid and supercritical CO2. A cyclic deposition process is presented properties of supercritical CO2 can aid in the delivery of precursors and in the removal of byproducts

  15. 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.

  16. 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.

  17. 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.

  18. [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.

  19. Flexible metallic seal for transition duct in turbine system

    SciTech Connect (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.

  20. Metal oxides for efficient infrared to visible upconversion

    E-Print Network [OSTI]

    Etchart, Isabelle

    2010-10-12

    Department of Materials Science and Metallurgy Metal Oxides for Efficient Infrared to Visible Upconversion Isabelle Etchart Corpus Christi College A dissertation submitted for the degree of Doctor of Philosophy Preface i... to the investigation of lanthanide-doped metal oxide hosts due to their good chemical, thermal and mechanical stabilities. Chapter 1 : General i ntroductio n 4 1 .4 . Previo us w ork In this thesis, we present results obtained on Y 2...

  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. 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.

  3. 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.

  4. Enhanced Half-Metallicity in Edge-Oxidized Zigzag Graphene

    E-Print Network [OSTI]

    Hod, Oded

    Enhanced Half-Metallicity in Edge-Oxidized Zigzag Graphene Nanoribbons Oded Hod,* Vero´nica Barone theoretical study of the electronic properties and relative stabilities of edge-oxidized zigzag graphene with nanometer scale dimen- sions. Recently, a new type of graphene-based material was experimentally realized.12

  5. 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.

  6. 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.

  7. Fracture Toughness of Metallic Glasses: Ductile-to-Brittle Transition?

    E-Print Network [OSTI]

    Rycroft, Chris H

    2012-01-01

    Quantitative understanding of the fracture toughness of metallic glasses, including the associated ductile-to-brittle transitions, is not yet available. Here we use a simple model of plastic deformation in glasses, coupled to an advanced Eulerian level set formulation for solving complex free boundary problems, to calculate the fracture toughness of metallic glasses as a function of the degree of structural relaxation corresponding to different annealing times near the glass temperature. Our main result indicates the existence of an elasto-plastic crack tip instability for sufficiently relaxed glasses, resulting in a marked drop in the toughness, which we interpret as a ductile-to-brittle transition similar to experimental observations.

  8. Aerosol chemical vapor deposition of metal oxide films

    DOE Patents [OSTI]

    Ott, K.C.; Kodas, T.T.

    1994-01-11

    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 substrate.

  9. High temperature superconductivity in metallic region near Mott transition

    E-Print Network [OSTI]

    Tian De Cao

    2009-09-11

    The spin-singlet superconductivity without phonons is examined in consideration of correlations on an extended Hubbard model. It is shown that the superconductivity requires not only the total correlation should be strong enough but also the density of state around Fermi energy should be large enough, which shows that the high temperature superconductivity could only be found in the metallic region near the Mott metal insulator transition (MIT). Other properties of superconductors are also discussed on these conclusions.

  10. Ultrathin amorphous zinc-tin-oxide buffer layer for enhancing heterojunction interface quality in metal-oxide solar cells

    E-Print Network [OSTI]

    Heo, Jaeyeong

    We demonstrate a tunable electron-blocking layer to enhance the performance of an Earth-abundant metal-oxide solar-cell material. A 5 nm thick amorphous ternary metal-oxide buffer layer reduces interface recombination, ...

  11. 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.

  12. 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.

  13. Hall effect at a tunable metal-insulator transition 

    E-Print Network [OSTI]

    Teizer, Winfried; Hellman, F.; Dynes, RC.

    2003-01-01

    Using a rotating magnetic field, the Hall effect in three-dimensional amorphous GdxSi1-x has been measured in the critical regime of the metal-insulator transition for a constant total magnetic field. The Hall coefficient R-0 is negative, indicating...

  14. Electrical characterization of native-oxide InAlPGaAs metal-oxide-semiconductor heterostructures using

    E-Print Network [OSTI]

    Electrical characterization of native-oxide InAlPÕGaAs metal-oxide-semiconductor heterostructures 8 December 2003; accepted 20 January 2004 InAIP native oxide/GaAs metal-oxide-semiconductor MOS of Schottky gates can lead to excessive gate leakage current and also restrict the forward gate bias to only

  15. Slow Magnetic Relaxation in Multinuclear Coordination Clusters and Low-Coordinate Transition Metal Complexes

    E-Print Network [OSTI]

    Zadrozny, Joseph Mercer

    2013-01-01

    lend themselves to bearing large magnetic anisotropies.bearing second– and third–row transition metals as the pendant metal centers, thereby providing a route to stronger magnetic

  16. Comparative study of metal or oxide capped indiumtin oxide anodes for organic light-emitting diodes

    E-Print Network [OSTI]

    of Physics. DOI: 10.1063/1.1556184 I. INTRODUCTION Organic light-emitting diodes OLEDs 1 are challengingComparative study of metal or oxide capped indium­tin oxide anodes for organic light as anodes in organic light-emitting diodes based on N,N -diphenyl-N,N bis 3-methyl-phenyl-1,1 -biphenyl-4

  17. 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

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

    Office of Scientific and Technical Information (OSTI)

    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...

  19. 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.

  20. Disordered electronic and magnetic systems - transition metal (Mn) and rare earth (Gd) doped amorphous group IV semiconductors (C, Si, Ge)

    E-Print Network [OSTI]

    Zeng, Li

    2007-01-01

    various transition or rare-earth metals provide a rich ?eldTransition Metal (Mn) and Rare Earth (Gd) Doped AmorphousTransition Metal (Mn) and Rare Earth (Gd) Doped Amorphous

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

    Office of Scientific and Technical Information (OSTI)

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

  2. 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.

  3. A superconductor to superfluid phase transition in liquid metallic hydrogen

    E-Print Network [OSTI]

    Egor Babaev; Asle Sudbo; N. W. Ashcroft

    2004-10-18

    Although hydrogen is the simplest of atoms, it does not form the simplest of solids or liquids. Quantum effects in these phases are considerable (a consequence of the light proton mass) and they have a demonstrable and often puzzling influence on many physical properties, including spatial order. To date, the structure of dense hydrogen remains experimentally elusive. Recent studies of the melting curve of hydrogen indicate that at high (but experimentally accessible) pressures, compressed hydrogen will adopt a liquid state, even at low temperatures. In reaching this phase, hydrogen is also projected to pass through an insulator-to-metal transition. This raises the possibility of new state of matter: a near ground-state liquid metal, and its ordered states in the quantum domain. Ordered quantum fluids are traditionally categorized as superconductors or superfluids; these respective systems feature dissipationless electrical currents or mass flow. Here we report an analysis based on topological arguments of the projected phase of liquid metallic hydrogen, finding that it may represent a new type of ordered quantum fluid. Specifically, we show that liquid metallic hydrogen cannot be categorized exclusively as a superconductor or superfluid. We predict that, in the presence of a magnetic field, liquid metallic hydrogen will exhibit several phase transitions to ordered states, ranging from superconductors to superfluids.

  4. Holographic Polarons, the Metal-Insulator Transition and Massive Gravity

    E-Print Network [OSTI]

    Matteo Baggioli; Oriol Pujolas

    2014-11-19

    Massive gravity is holographically dual to `realistic' materials with momentum relaxation. The dual graviton potential encodes the phonon dynamics and it allows for a much broader diversity than considered so far. We construct a simple family of isotropic and homogeneous materials that exhibit an interaction-driven Metal-Insulator transition. The transition is triggered by the formation of polarons -- phonon-electron quasi-bound states that dominate the conductivities, shifting the spectral weight above a mass gap. We characterize the polaron gap, width and dispersion.

  5. Transition Metal Dimer Internuclear Distances from Measured Force Constants Joseph L. Jules and John R. Lombardi*

    E-Print Network [OSTI]

    Lombardi, John R.

    Transition Metal Dimer Internuclear Distances from Measured Force Constants Joseph L. Jules distances, have been extended to the transition metal dimers to test which one gives the most accurate fit's and Guggenheimer's for the transition metal dimers. Although Pauling's rule gives the best results, the remarkable

  6. 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.

  7. Ductile-to-brittle transition in spallation of metallic glasses

    SciTech Connect (OSTI)

    Huang, X. [State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190 (China); Institute of Systems Engineering, China Academy of Engineering Physics, Mianyang, Sichuan 621999 (China); Ling, Z. [State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190 (China); Dai, L. H., E-mail: lhdai@lnm.imech.ac.cn [State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190 (China); State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 10081 (China)

    2014-10-14

    In this paper, the spallation behavior of a binary metallic glass Cu{sub 50}Zr{sub 50} is investigated with molecular dynamics simulations. With increasing the impact velocity, micro-voids induced by tensile pulses become smaller and more concentrated. The phenomenon suggests a ductile-to-brittle transition during the spallation process. Further investigation indicates that the transition is controlled by the interaction between void nucleation and growth, which can be regarded as a competition between tension transformation zones (TTZs) and shear transformation zones (STZs) at atomic scale. As impact velocities become higher, the stress amplitude and temperature rise in the spall region increase and micro-structures of the material become more unstable. Therefore, TTZs are prone to activation in metallic glasses, leading to a brittle behavior during the spallation process.

  8. 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

  9. Metal Oxide Semiconductor Gas Sensors and Neural Networks

    E-Print Network [OSTI]

    Siegel, Mel

    Olfaction Metal Oxide Semiconductor Gas Sensors and Neural Networks M. W. Siegel Carnegie Mellon around a chemical plant, sniffing as it goes for gas leaks (or the vapors of liquid leaks), navigating perhaps directed to the offending pipe fissure or open valve by acoustic homing toward the source

  10. 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.

  11. Structure of liquid transition and rare earth metals S. N. Khanna and F. Cyrot-Lackmann

    E-Print Network [OSTI]

    Boyer, Edmond

    L-45 Structure of liquid transition and rare earth metals S. N. Khanna and F. Cyrot-Lackmann Groupe It is shown that the observed structure factors of transition and rare earth liquid metals can be reaso- nably. The difference is particularly large for V, Ti, and rare earth metals which are precisely the metals where

  12. 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.

  13. Reduction of Metal Oxides by Microwave Heating of Multi-walled...

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

    Reduction of Metal Oxides by Microwave Heating of Multi-walled Carbon Nanotubes Microwave heating of a metal oxide in the presence of multi-walled carbon nanotubes may result in...

  14. Electrical excitation of colloidally synthesized quantum dots in metal oxide structures

    E-Print Network [OSTI]

    Wood, Vanessa Claire

    2010-01-01

    This thesis develops methods for integrating colloidally synthesized quantum dots (QDs) and metal oxides in optoelectronic devices, presents three distinct light emitting devices (LEDs) with metal oxides surrounding a QD ...

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

    SciTech Connect (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.

  17. Holographic metal/superconductor phase transitions with dark matter sector

    E-Print Network [OSTI]

    Peng, Yan

    2015-01-01

    In this paper, we investigate the holographic phase transitions with dark matter sector in the AdS black hole background away from the probe limit. We firstly detect the formation of the scalar hair by examining the behaviors of the superconducting solutions and the effective mass of the scalar field. Then we study the condensation of the scalar operator with respect to the Hawking temperature T. As a further step, we disclose the properties of the phase transitions from the holographic topological entanglement entropy of the system. The holographic topological entanglement entropy is proved to be very useful in characterizing the difference between various phases. At last, we also derive the qualitative properties through the analytical methods. In summary, we find that the model parameters can provide rich physics in the general holographic metal/superconductor phase transitions.

  18. 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.

  19. 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.

  20. Nanotube Formation: Researchers Learn To Control The Dimensions Of Metal Oxide Nanotubes

    E-Print Network [OSTI]

    Nair, Sankar

    made from metal oxides -- work that could lead to a technique for precisely conNanotube Formation: Researchers Learn To Control The Dimensions Of Metal Oxide Nanotubes Science their diameter and length. Based on metal oxides in combination with silicon and germanium, such single

  1. Catalytic oxidation of CO by platinum group metals: from ultrahigh vacuum to elevated pressures

    E-Print Network [OSTI]

    Goodman, Wayne

    oxidation over platinum group metals has been investigated for some eight decades by many researchersCatalytic oxidation of CO by platinum group metals: from ultrahigh vacuum to elevated pressures A Catalytic oxidation of CO over platinum group metals (Pt, Ir, Rh and Pd) has been the subject of many

  2. Direct probe of Mott-Hubbard to charge-transfer insulator transition and electronic structure evolution in transition-metal systems

    SciTech Connect (OSTI)

    Olalde-Velasco, P; Jimenez-Mier, J; Denlinger, JD; Hussain, Z; Yang, WL

    2011-07-11

    We report the most direct experimental verification of Mott-Hubbard and charge-transfer insulators through x-ray emission spectroscopy in transition-metal (TM) fluorides. The p-d hybridization features in the spectra allow a straightforward energy alignment of the anion-2p and metal-3d valence states, which visually shows the difference between the two types of insulators. Furthermore, in parallel with the theoretical Zaanen-Sawatzky-Allen diagram, a complete experimental systematics of the 3d Coulomb interaction and the 2p-3d charge-transfer energy is reported and could serve as a universal experimental trend for other TM systems including oxides.

  3. 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.

  4. Voltage oxide removal for plating: A new method of electroplating oxide coated metals in situ

    SciTech Connect (OSTI)

    Gutfeld, R. J. von; West, A. C. [Department of Chemical Engineering, Columbia University, New York, New York 10027 (United States)

    2007-03-15

    A novel in situ method for electroplating oxide coated metals is described. Termed VORP, for voltage oxide removal for plating, the process utilizes a voltage pulse {approx}20-200 V, {approx}2 ms in duration, applied between working and counterelectrodes while both are immersed in a copper electrolyte. The pulse is almost immediately followed by galvanostatic plate-up. Adherent copper deposits up to {approx}4 {mu}m in height on stainless steel 316 coupons have been obtained. Temperature testing up to 260 deg. C in air does not affect the copper adhesion. A preliminary model for oxide removal is proposed utilizing concepts of dielectric breakdown.

  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. 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.

  7. 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.

  8. Study of the spray to globular transition in gas metal arc welding: a spectroscopic investigation

    E-Print Network [OSTI]

    Study of the spray to globular transition in gas metal arc welding: a spectroscopic investigation of the spray to globular transition in gas metal arc welding: a spectroscopic investigation F Valensi1.iop.org/JPhysD/46/224005 Abstract The gas metal arc welding (GMAW) process is strongly influenced by the composition

  9. 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.

  10. 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.

  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 (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.

  12. 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.

  13. 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.

  14. Reactions of S-nitrosothiols with biomimetic iron complexes and other transition metals

    E-Print Network [OSTI]

    Victor, Eric, Ph. D. Massachusetts Institute of Technology

    2014-01-01

    Chapter 1. Bioinorganic Chemistry of Nitric Oxide and S-Nitrosothiols The interplay of nitric oxide (NO), biological thiols, and metals has been a topic of intense study since the discovery of NO as the endothelium-derived ...

  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. Metal-ion catalyzed oxidation of a G-agent simulant by oxone. Final report Oct 89-Dec 90

    SciTech Connect (OSTI)

    Leslie, D.R.; Ward, J.R.

    1992-07-01

    By means of the ability of oxone to oxidize sulphur, oxone has been shown to be a rapid decontaminant for mustard or VX. G-agents, such as sarin or soman, are difficult to oxidize, and all means to decontaminate sarin or soman are based on hydrolysis. To see if oxone might have utility as a general decontaminant, experiments were run to see if the ability of oxone to destroy organophosphorus esters could be enhanced with transition-metal catalysts. Hydrolysis of the G-agent simulant diisopropyl methylphosphonate (DIMP) was promoted in oxone solution by the presence of such low valent metal ions as cobalt (II), chromium (III), or manganese (II). The reaction is initiated by radical formation from decomposition of HO-SO3. Radical chains may be terminated by dimerization of S04-, other reactions forming 02, or by reduction of the radical to S04= by low valent metal ion. The radical can also reduce the oxidized metal ion back to the original low valent state, thereby providing a path for turnover of the metal ion. The relatively slow rate and the potential for contaminants in field application that could react with the SO4- radicals make it unlikely that metal ion catalysis of oxone decomposition will prove to be a useful decontaminant. Decontamination, NMR, Chemical agents, Metal-ion catalysis, Chromium (III), DIMP, Oxone, Kinetics. This paper describes the effect of a crystal field, according to site symmetry, upon the magnetic quantum-level structure of an atomic ion, as expressed in electric dipole transitions (a corresponding treatment for magnetic dipole transitions, in the original German, is not included). Crystal field Magnetic quantum numbers Atomic ion.

  17. 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.

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

    Office of Science (SC) Website

    Insulator-to-Metal Transition of Vanadium Dioxide Advanced Scientific Computing Research (ASCR) ASCR Home About Research Facilities Science Highlights Benefits of ASCR Funding...

  20. 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,...

  1. Illumination induced charge separation at tetraphenyl-porphyrin/metal oxide interfaces

    E-Print Network [OSTI]

    Shapira, Yoram

    Illumination induced charge separation at tetraphenyl-porphyrin/metal oxide interfaces Y. Zidon were studied at tetraphenyl-porphyrin H2TPP /metal oxide interfaces by surface photovoltage spectroscopy. The thickness of the depleted Ti and Sn oxide layers was about 2 nm. Acceptorlike interface

  2. 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

  3. 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

  4. 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

  5. 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.

  6. 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

  7. 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.

  8. 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

  9. Metal-based turn-on fluorescent probes for nitric oxide sensing

    E-Print Network [OSTI]

    Lim, Mi Hee

    2006-01-01

    Chapter 1. Metal-Based Turn-On Fluorescent Probes for Sensing Nitric Oxide. Nitric oxide, a reactive free radical, regulates a variety of biological processes. The absence of tools to detect NO directly, rapidly, specifically ...

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. Spillover-Assisted Hydrogen Evolution at Si-based Metal-Oxide...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Spillover-Assisted Hydrogen Evolution at Si-based Metal-Oxide-Semiconductor Photoelectrodes. Citation Details In-Document Search Title: Spillover-Assisted Hydrogen...

  15. Project Profile: Thermochemical Heat Storage for CSP Based on Multivalent Metal Oxides

    Broader source: Energy.gov [DOE]

    General Atomics (GA), under the Thermal Storage FOA, is developing a high-density thermochemical heat storage system based on solid metal oxides.

  16. 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.

  17. 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.

  18. 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.

  19. 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).

  20. Chemically Modified Metal Oxide Nanostructure for Photoelectrochemical Water Splitting

    E-Print Network [OSTI]

    Wang, Gongming

    2013-01-01

    be good catalysts for catalytic oxidation of small organicsolution, indicative of catalytic oxidation of urea presentactive catalytic species for water oxidation. The catalytic

  1. The carburization of transition metal molybdates (MxMoO?, M= Cu, Ni or Co) and the generation of highly active metal/carbide catalysts for CO? 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/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 Cu²?, Ni²? and Co²? cations inside each molybdate. The synthesized Cu/Mo?C, Ni/Mo?C and Co/Mo?C catalysts were highlymore »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).« less

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

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

    Rodriguez, Jose A. [Brookhaven National Lab. (BNL), Upton, NY (United States); Xu, Wenqian [Brookhaven National Lab. (BNL), Upton, NY (United States); Ramirez, Pedro J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Univ. Central De Venezuela, Caracas (Venesuela); Stachiola, Dario [Brookhaven National Lab. (BNL), Upton, NY (United States); Brito, Joaquin L. [Inst. Venezolano de Investigaciones Cientificas, Caracas (Venezuela)

    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 Cu²?, Ni²? and Co²? 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).

  3. 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.

  4. 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 Na?O 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

  5. Non-equilibrium oxidation states of zirconium during early stages of metal oxidation Wen Ma, F. William Herbert, Sanjaya D. Senanayake, and Bilge Yildiz

    E-Print Network [OSTI]

    Yildiz, Bilge

    Non-equilibrium oxidation states of zirconium during early stages of metal oxidation Wen Ma, F.1116/1.4792068 The initial, thermal oxidation of zirconium at room temperature J. Appl. Phys. 96, 7126 (2004); 10 of zirconium during early stages of metal oxidation Wen Ma,1 F. William Herbert,1,2 Sanjaya D. Senanayake,3

  6. 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).

  7. Atomic Layer Deposition of Hafnium and Zirconium Oxides Using Metal Amide Precursors

    E-Print Network [OSTI]

    Atomic Layer Deposition of Hafnium and Zirconium Oxides Using Metal Amide Precursors Dennis M (ALD) of smooth and highly conformal films of hafnium and zirconium oxides was studied using six metal alkylamide precursors for hafnium and zirconium. Water was used as an oxygen source during these experiments

  8. 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.

  9. 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.

  10. Metal oxide morphology in argon-assisted glancing angle deposition

    SciTech Connect (OSTI)

    Sorge, J. B.; Taschuk, M. T.; Wakefield, N. G.; Sit, J. C.; Brett, M. J. [Department of Electrical and Computer Engineering, University of Alberta, Edmonton, AB T6G 2V4 (Canada); Department of Electrical and Computer Engineering, University of Alberta, Edmonton, AB T6G 2V4 (Canada) and NRC National Institute for Nanotechnology, Edmonton, AB T6G 2M9 (Canada)

    2012-03-15

    Glancing angle deposition (GLAD) is a thin film deposition technique capable of fabricating columnar architectures such as posts, helices, and chevrons with control over nanoscale film features. Argon bombardment during deposition modifies the GLAD process, producing films with new morphologies which have shown promise for sensing and photonic devices. The authors report modification of column tilt angle, film density, and specific surface area for 12 different metal oxide and fluoride film materials deposited using Ar-assisted GLAD. For the vapor flux/ion beam geometry and materials studied here, with increasing argon flux, the column tilt increases, film density increases, and specific surface area decreases. With a better understanding of the nature of property modification and the mechanisms responsible, the Ar-assisted deposition process can be more effectively targeted towards specific applications, including birefringent thin films or photonic crystal square spirals.

  11. Magnetic ground state of semiconducting transition metal trichalcogenide monolayers

    SciTech Connect (OSTI)

    Sivadas, Mr. Nikhil [Carnegie Mellon University (CMU); Daniels, Matthew W. [Carnegie Mellon University (CMU); Swendsen, Robert H. [Carnegie Mellon University (CMU); Okamoto, Satoshi [ORNL; Xiao, Di [Carnegie Mellon University (CMU)

    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.

  12. EURODISPLAY 2002 631 P-64: A Comparative Study of Metal Oxide Coated Indium-tin Oxide Anodes

    E-Print Network [OSTI]

    over that of a conventional OLED without an oxide capped anode. 1. Introduction Organic light for Organic Light-emitting Diodes Chengfeng Qiu, Haiying Chen, Zhilang Xie, Man Wong and Hoi Sing Kwok Center of metals enhance while other oxides degrade the hole-injection and quantum efficiencies of organic light

  13. Models for transition metal oxides and for protein design

    E-Print Network [OSTI]

    Zhou, Fei, Ph. D. Massachusetts Institute of Technology

    2006-01-01

    A large number of properties of solid state materials can now be predicted with standard first-principles methods such as the Local Density (LDA) or Generalized Gradient Approximation (GGA). However, known problems exist ...

  14. Copyright A. J. Millis 2013 Columbia University Transition Metal Oxides

    E-Print Network [OSTI]

    Millis, Andrew

    .353 5.6437 5.244 Lutetium 6.146 5.5769 6.689 5.5387 6.64 5.473 7.01 5.5250 7.264 Holmium Erbium Thulium

  15. Transition metal oxides on organic semiconductors Yongbiao Zhao a

    E-Print Network [OSTI]

    Xiong, Qihua

    inverted organic light-emitting diodes (OLEDs) and inverted organic solar cells (OSCs), which can improve of organic semiconductors (OSs). For example, in organic light-emitting diodes (OLEDs) [7], they are used! Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic

  16. Superconductors and Complex Transition Metal Oxides for Tunable THz

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail. (Conference)Feedback System inStatusand carbon structuresConnectPlasmonic

  17. Superconductors and Complex Transition Metal Oxides for Tunable THz

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail. (Conference)Feedback System inStatusand carbon

  18. 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.

  19. 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.

  20. 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.

  1. Characterization of Pt-based Transition Metal Alloy Electrodes for PEFC

    SciTech Connect (OSTI)

    Uebayashi, M.; Sato, Y.; Jeyadevan, B.; Tohji, K. [Graduate School of Environmental Studies, Tohoku Univ., Aramaki aza Aoba, Aoba-ku, Sendai (Japan); Sawada, Y. [Sumitomo Corporation, 1-8-11, Harumi, Chuo-ku, Tokyo 104-8610 (Japan); Itoh, T. [Center for Interdisciplinary Research, Tohoku Univ., Aramaki aza Aoba, Aoba-ku, Sendai (Japan)

    2007-03-20

    Pt metal is generally used as electrocatalyst in polymer electrolyte fuel cells (PEFC). However, the catalytic action of Pt anode is obstructed by the adsorption of CO gas molecules on to their surface and consequently the efficiency of the fuel cell decreases. Moreover, the activity of PEFC deteriorates even if the presence of CO is as low as 100 ppm. In this paper, attempts are being made to replace the Pt with Pt-based transition metal alloys such as PtFe and PtCo to overcome the above problem and also to improve the activity of fuel cells. The PtFe/C and PtCo/C necessary for the preparation of the electrodes were synthesized by depositing PtFe and PtCo particles synthesized using the polyol process on to the surface ketjenblack. From the results of cyclic voltammetry, we could confirm that PtFe/C could be used as an alternate material of Pt/C. However, Fe ions get eluted in the electrolyte. Thus, the study that can control the elution of Fe ion is necessary. Also in case of PtCo/C, we could confirm that Co ion doesn't get to elute, however the hydrogen oxidation reaction current is quite low.

  2. Nitric Oxide in Biological Denitrification: Fe/Cu Metalloenzyme and Metal Complex NOx Redox Chemistry

    E-Print Network [OSTI]

    Schroeder, Imke

    Nitric Oxide in Biological Denitrification: Fe/Cu Metalloenzyme and Metal Complex NOx Redox Nitrite Reductase: 1204 2. Copper Nitrite Reductases 1206 B. Nitric Oxide Reductase 1208 1. Structure 1208 Nitric Oxide Sensors, Scavengers, and Delivery Agents 1227 IV. Concluding Remarks 1229 V. Acknowledgments

  3. 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.

  4. 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.

  5. 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.

  6. Syntheses and applications of soluble polyisobutylene (PIB)-supported transition metal catalysts 

    E-Print Network [OSTI]

    Tian, Jianhua

    2009-05-15

    Soluble polymer supports facilitate the recovery and recycling of expensive transition metal complexes. Recently, polyisobutylene (PIB) oligomers have been found to be suitable polymer supports for the recovery of a variety ...

  7. Zwitterionic late transition metal alkene polymerisation catalysts containing aminofulvene-aldiminate (AFA) ligands 

    E-Print Network [OSTI]

    Rahman, Mohammed Mahmudur

    2010-01-01

    Over recent years significant progress has been made in the design and development of late transition metal cationic catalysts for olefin polymerisation. Never-the-less, the activation of catalyst precursors and generation ...

  8. The Use of Soluble Polyolefins as Supports for Transition Metal Catalysts 

    E-Print Network [OSTI]

    Hobbs, Christopher Eugene

    2012-10-19

    The use of polymer supports for transition metal catalysts are very important and useful in synthetic organic chemistry as they make possible the separation and isolation of catalysts and products quite easy. These ...

  9. Tin, Antimony, Bismuth, and Tellurium Lewis Acids in sigma-Accepting Ligands for Transition Metals 

    E-Print Network [OSTI]

    Lin, Tzu-Pin

    2012-10-19

    The interactions between ligands and transition metals have been an essential subject in inorganic chemistry. Other than the commonly known L-type (two-electron donors) and X-type ligands (one-electron donors), Z-type ...

  10. Transition metal gettering studies and simulation for the optimization of silicon photovoltaic device processing

    E-Print Network [OSTI]

    Smith, Aimée Louise, 1971-

    2002-01-01

    We use what is known about transition metal (TM) defect thermodynamic driving forces and kinetic responses to make predictive simulation of gettering during solar cell fabrication possible. We have developed a simulator ...

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. Metal Oxide Nanostructured Materials for Optical and Energy Applications

    E-Print Network [OSTI]

    Moore, Michael Christopher

    2013-01-01

    of a Stack of Two Metal Micromeshes. The Journal of Physicalals 3, 601 (2004). M. T. Hill et al. Lasing in metal-insulator-metal sub-wavelength plasmonic waveguides. Optics

  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. 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.

  2. Electronically conductive ceramics for high temperature oxidizing environments

    DOE Patents [OSTI]

    Kucera, G.H.; Smith, J.L.; Sim, J.W.

    1983-11-10

    This invention pertains to 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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?Å-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.

  8. Hydrothermally Stable, Sulfur-Tolerant Platinum-Based Oxidation Catalysts via Surface Modification of SiO2 with TiO2 and ZrO2

    Broader source: Energy.gov [DOE]

    This study demonstrates the feasibility of developing highly stable, sulfur-tolerant oxidation catalysts that use less Pt via surface modification of silica supports with transition metal oxides.

  9. 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.

  10. Universal quantum criticality in the metal-insulator transition of two-dimensional interacting Dirac electrons

    E-Print Network [OSTI]

    Yuichi Otsuka; Seiji Yunoki; Sandro Sorella

    2015-10-29

    The metal-insulator transition has been a subject of intense research since Nevil Mott has first proposed that the metallic behavior of interacting electrons could turn to the insulating one as electron correlations increase. Here, we consider electrons with massless Dirac-like dispersion in two spatial dimensions, described by the Hubbard models on two geometrically different lattices, and perform numerically exact calculations on unprecedentedly large systems that, combined with a careful finite size scaling analysis, allow us to explore the quantum critical behavior in the vicinity of the interaction-driven metal-insulator transition. We find thereby that the transition is continuous and determine the quantum criticality for the corresponding universality class, which is described in the continuous limit by the Gross-Neveu model, a model extensively studied in quantum field theory. We furthermore discuss a fluctuation-driven scenario for the metal-insulator transition in the interacting Dirac electrons: the metal-insulator transition is triggered only by the vanishing of the quasiparticle weight but not the Dirac Fermi velocity, which instead remains finite near the transition. This important feature cannot be captured by a simple mean-field or Gutzwiller-type approximate picture, but is rather consistent with the low energy behavior of the Gross-Neveu model.

  11. Fabrication of Metal/Oxide Nanostructures by Anodization Processes for Biosensor, Drug Delivery and Supercapacitor Applications 

    E-Print Network [OSTI]

    Chen, Po-Chun

    2014-01-13

    This dissertation proposed to initiate the research into the fabrication of metal/oxide nanostructures by anodization process for biosensor, drug delivery and supercapacitor applications by producing different nanostructures ...

  12. Design and construction of rigs for studying surface condensation and creating anodized metal oxide surfaces

    E-Print Network [OSTI]

    Sun, Wei-Yang

    2011-01-01

    This thesis details the design and construction of a rig for studying surface condensation and a rig for creating anodized metal oxides (AMOs). The condensation rig characterizes condensation for different surfaces; this ...

  13. Near-infrared photodetector consisting of J-aggregating cyanine dye and metal oxide thin films

    E-Print Network [OSTI]

    Osedach, Timothy P.

    We demonstrate a near-infrared photodetector that consists of a thin film of the J-aggregating cyanine dye, U3, and transparent metal-oxide charge transport layers. The high absorption coefficient of the U3 film, combined ...

  14. Low temperature lithographically patterned metal oxide transistors for large area electronics

    E-Print Network [OSTI]

    Wang, Annie I. (Annie I-Jen), 1981-

    2011-01-01

    Optically transparent, wide bandgap metal oxide semiconductors are a promising candidate for large-area electronics technologies that require lightweight, temperature-sensitive flexible substrates. Because these thin films ...

  15. 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.

  16. Water growth on metals and oxides: binding, dissociation and role of hydroxyl groups

    E-Print Network [OSTI]

    Salmeron, M.

    2008-01-01

    Note: In this paper the water structures formed are due toand correspond to a second water layer, not the first (seeWater growth on metals and oxides: binding, dissociation and

  17. Electronic Structure and Properties of Transition Metal-Benzene Ravindra Pandey, Bijan K. Rao,*, Purusottam Jena, and Miguel Alvarez Blanco

    E-Print Network [OSTI]

    Pandey, Ravi

    Electronic Structure and Properties of Transition Metal-Benzene Complexes Ravindra Pandey, Bijan Kd transition metal atoms (M) interacting with benzene molecules (Bz) is carried out using density. The variation of the metal-benzene distances, dissociation energies, ionization potentials, electron affinities

  18. 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 ?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.« less

  19. 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.

  20. TRANSITION METAL ACTIVATION AND FUNCTIONALIZATION OF CARBON-HYDROGEN BONDS

    E-Print Network [OSTI]

    Jones, William D.

    . The success includes not only several new nickel, palladium, and platinum based metal systems of the type [M vs. dissociation vs. migration down the alkyl chain. By using deuterium labeling, we have been able

  1. 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.

  2. 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.

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

    DOE Patents [OSTI]

    Marks, Tobin J. (Evanston, IL); Luo, Lubin (Baton Rouge, LA); Yoon, Sung Cheol (Evanston, IL)

    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.

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

    DOE Patents [OSTI]

    Marks, Tobin J. (Evanston, IL); Luo, Lubin (Baton Rouge, LA); Yoon, Sung Cheol (Evanston, IL)

    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.

  5. 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.

  6. 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.

  7. Analytica Chimica Acta 573574 (2006) 913 Metal oxide thin films as sensing layers for ozone detection

    E-Print Network [OSTI]

    2006-01-01

    Analytica Chimica Acta 573­574 (2006) 9­13 Metal oxide thin films as sensing layers for ozone. Their structural, electrical and ozone sensing properties were analyzed. Structural investigations carried out with ultraviolet light and subsequent oxidation in ozone atmosphere at room temperature. © 2006 Elsevier B.V. All

  8. Mercury Removal from Aqueous Systems Using Commercial and Laboratory Prepared Metal Oxide Nanoparticles 

    E-Print Network [OSTI]

    Desai, Ishan

    2010-10-12

    Five commercial metal oxide nanoparticles (CuO, SiO2, Fe2O3, TiO2 and Al2O3) have been individually screened for mercury removal in a batch reactor under bicarbonate buffered and non-buffered aqueous solutions (DI water). Copper oxide...

  9. 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.

  10. Aliovalent Substitution in Mixed Ni-Mn-Co Oxide Cathodes

    E-Print Network [OSTI]

    Kam, Kinson C.

    2012-01-01

    batteries, cathode, transition metal oxides, aliovalent substitution Acknowledgment This work was supported by the Assistant Secretary for Energy Efficiency and Renewable

  11. A general holographic metal/superconductor phase transition model

    E-Print Network [OSTI]

    Yan Peng; Yunqi Liu

    2015-03-03

    We study the scalar condensation of a general holographic superconductor model in AdS black hole background away from the probe limit. We find the model parameters together with the scalar mass and backreaction can determine the order of phase transitions completely. In addition, we observe two types of discontinuities of the scalar operator in the case of first order phase transitions. We analyze in detail the effects of the scalar mass and backreaction on the formation of discontinuities and arrive at an approximate relation between the threshold model parameters. Furthermore, we obtain superconductor solutions corresponding to higher energy states and examine the stability of these superconductor solutions.

  12. 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.

  13. 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.

  14. 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.

  15. On Transition Metal Catalyzed Reduction of N-nitrosodimethlamine

    E-Print Network [OSTI]

    Zhou, Jun; Tian, Junhua; Zhao, Zhun

    2014-01-01

    This report provides a critical review on "Metal-Catalyzed Reduction of N-Nitrosodimethylamine with Hydrogen in Water", by Davie et al. N-nitrosodimethlamine (NDMA) is a contaminant in drinking and ground water which is difficult to remove by conventional physical methods, such as air stripping. Based on the reported robust capability of metal based powder shaped catalysts in hydrogen reduction, several monometallic and bimetallic catalyst are studied in this paper on the reduction of NDMA with hydrogen. Two kinds of kinetics, metal weight normalized and surface area normalized, are compared between each catalyst in terms of pseudo-first order reaction rate. Palladium, copper enhanced palladium and nickel are found to be very efficient in NDMA reduction, with half-lives on the order of hours per 10 mg/l catalyst metal. Preliminary LC-MS data and carbon balance showed no intermediates. Finally, a simple hydrogen and NMDA surface activated reaction mechanism is proposed by the author for palladium and nickel.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. Gas-phase ultraviolet photoelectron spectroscopy and molecular orbital calculations on transition metal carbonyls and nitrosyls 

    E-Print Network [OSTI]

    Morris-Sherwood, Betty Jeanne

    1981-01-01

    the complexes are formally M(0) 3d 6 the calculations suggest that the "metal" electrons are highly delocalized onto the nitrosyls. This suggestion is supported by the similarity in the ionization energies of the chromium complexes to those... f t d tyj la~lao ~Ch 1 t? description of the molecular orbitals, which can be useful in under- standing the chemistry and bonding in transition metal complexes. The following study will apply PE spectroscopy and MO calcula- tions to derivatives...

  1. Steam Reforming on Transition-metal Carbides from Density-functional Theory

    SciTech Connect (OSTI)

    Vojvodic, Aleksandra

    2012-05-11

    A screening study of the steam reforming reaction on clean and oxygen covered early transition-metal carbides surfaces is performed by means of density-functional theory calculations. It is found that carbides provide a wide spectrum of reactivities, from too reactive via suitable to too inert. Several molybdenum-based systems are identified as possible steam reforming catalysts. The findings suggest that carbides provide a playground for reactivity tuning, comparable to the one for pure metals.

  2. 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.

  3. Chemically Modified Metal Oxide Nanostructure for Photoelectrochemical Water Splitting

    E-Print Network [OSTI]

    Wang, Gongming

    2013-01-01

    the reported solar conversion efficiency of hematitelead to a good solar conversion efficiency. 16, 24, 26, 27for urea oxidation, the solar conversion efficiency of TiO 2

  4. Metal catalyzed copolymerization processes involving carbon oxides as substrates 

    E-Print Network [OSTI]

    Phelps, Andrea Lee

    2005-11-01

    Studies concerning two different copolymerization processes are detailed in this dissertation: propylene oxide/CO2 coupling to afford poly(propylene carbonate) and Nbutylaziridine/ CO coupling to afford poly-??-butylalanoid. ...

  5. 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.

  6. Coherent/incoherent metal transition in a holographic model

    E-Print Network [OSTI]

    Keun-Young Kim; Kyung Kiu Kim; Yunseok Seo; Sang-Jin Sin

    2014-12-13

    We study AC electric($\\sigma$), thermoelectric($\\alpha$), and thermal($\\bar{\\kappa}$) conductivities in a holographic model, which is based on 3+1 dimensional Einstein-Maxwell-scalar action. There is momentum relaxation due to massless scalar fields linear to spatial coordinate. The model has three field theory parameters: temperature($T$), chemical potential($\\mu$), and effective impurity($\\beta$). At low frequencies, if $\\beta metal). The parameters of this modified Drude peak are obtained analytically. In particular, if $\\beta \\ll \\mu$ the relaxation time of electric conductivity approaches to $2\\sqrt{3} \\mu/\\beta^2$ and the modified Drude peak becomes a standard Drude peak. If $\\beta > \\mu$ the shape of peak deviates from the Drude form(incoherent metal). At intermediate frequencies($T<\\omega<\\mu$), we have analysed numerical data of three conductivities($\\sigma, \\alpha, \\bar{\\kappa}$) for a wide variety of parameters, searching for scaling laws, which are expected from either experimental results on cuprates superconductors or some holographic models. In the model we study, we find no clear signs of scaling behaviour.

  7. Notes on the photo-induced characteristics of transition metal-doped and undoped titanium dioxide thin films

    E-Print Network [OSTI]

    Cirkva, Vladimir

    Notes on the photo-induced characteristics of transition metal-doped and undoped titanium dioxide with a transition metal. The behavior of prepared films was described by means of their pho- tocatalytic and photo. All films were then tested for their photo-induced electrochemical properties based on evaluation

  8. Deep Hydrodesulfurization in Homogeneous Solution: Access to a Transition-Metal Insertion Complex of

    E-Print Network [OSTI]

    Jones, William D.

    Deep Hydrodesulfurization in Homogeneous Solution: Access to a Transition-Metal Insertion Complex has been focused on the problems of "deep" hydrodesulfurization (HDS) or production of gas oils is to find more active catalysts for deep HDS, and this challenge can be stated without much

  9. 1,2-Aryl and 1,2-Hydride Migration in Transition Metal Complex Catalyzed

    E-Print Network [OSTI]

    Wang, Jianbo

    1,2-Aryl and 1,2-Hydride Migration in Transition Metal Complex Catalyzed Diazo Decomposition of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Department of Chemistry, Peking Uni,2-hydride migration was studied. A reaction mechanism involving a "bridged" phenonium ion is proposed

  10. Hybrid Car-Parrinello/Molecular Mechanics Modelling of Transition Metal Complexes: Structure, Dynamics and Reactivity

    E-Print Network [OSTI]

    Guidoni, Leonardo

    Hybrid Car-Parrinello/Molecular Mechanics Modelling of Transition Metal Complexes: Structure). We have recently developed a QM/MM extension of a Car-Parrinello scheme [5]. These hybrid Car functional theory embedded in a classical force field description. The power of such a combined Car

  11. A Spectromicroscopic Study of 3d Transition Metal Interactions with Humic Acid; A bright

    E-Print Network [OSTI]

    Sparks, Donald L.

    A Spectromicroscopic Study of 3d Transition Metal Interactions with Humic Acid; A bright future for Humic Acid Research? (S02- nachtegaal174813-Oral) Abstract: It is important to understand groups of humic acid. Soft X-ray microscopy was applied to map the distribution of carbon containing

  12. Super hard cubic phases of period VI transition metal nitrides: First principles investigation

    E-Print Network [OSTI]

    Khare, Sanjay V.

    and shear modulus for stable phases, potential hard coating materials for cutting tools have been identified July 2008 Keywords: Coatings Elastic properties Hardness Nitrides We report a systematic study B.V. All rights reserved. 1. Introduction Hard coatings of many transition metal nitrides have

  13. Transition metal co-precipitation mechanisms in silicon T. Buonassisi a,*, M. Heuer a,1

    E-Print Network [OSTI]

    Transition metal co-precipitation mechanisms in silicon T. Buonassisi a,*, M. Heuer a,1 , A Available online 18 September 2007 Abstract Formation mechanisms of precipitates containing multiple by synchrotron-based X-ray microprobe techniques. Precipitates formed at low (655 °C) and high (1200 °C

  14. 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.

  15. 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.

  16. 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.

  17. Holographic entanglement entropy in metal/superconductor phase transition with Born-Infeld electrodynamics

    E-Print Network [OSTI]

    Weiping Yao; Jiliang Jing

    2014-08-11

    We investigate the holographic entanglement entropy in the metal/superconductor phase transition for the Born-Infeld electrodynamics with full backreaction and note that the entropy is a good probe to study the properties of the phase transition. For the operator $$, we find that the entanglement entropy decreases (or increases) with the increase of the Born-Infeld parameter $b$ in the metal (or superconducting) phase. For the operator $$, we observe that, with the increase of the Born-Infeld parameter, the entanglement entropy in the metal phase decreases monotonously but the entropy in the superconducting phase first increases and forms a peak at some threshold $b_{T}$, then decreases continuously. Moreover, the value of $b_{T}$ becomes smaller as the width of the subsystem $A$ decreases.

  18. 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.

  19. 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.

  20. Noble Metal Catalysts for Mercury Oxidation in Utility Flue Gas: Gold, Palladium and Platinum Formulations

    SciTech Connect (OSTI)

    Presto, A.A.; Granite, E.J

    2008-07-01

    The use of noble metals as catalysts for mercury oxidation in flue gas remains an area of active study. To date, field studies have focused on gold and palladium catalysts installed at pilot scale. In this article, we introduce bench-scale experimental results for gold, palladium and platinum catalysts tested in realistic simulated flue gas. Our initial results reveal some intriguing characteristics of catalytic mercury oxidation and provide insight for future research into this potentially important process.

  1. 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.

  2. Distinct Length Scales in the VO{sub 2} Metal–Insulator Transition Revealed by Bi-chromatic Optical Probing

    SciTech Connect (OSTI)

    Wang, Lei [College of William and Mary, Williamsburg, VA (United States); Novikova, Irina B. [College of William and Mary, Williamsburg, VA (United States); Klopf, John M. [JLAB, Newport News, VA (United States); Madaras, Scott E. [JLAB, Newport News, VA (United States); Williams, Gwyn P. [College of William and Mary, Williamsburg, VA (United States); Madaras, Eric [Nasa Langley Research Center, Hampton, VA (United States); Lu, Liwei [Univ. of Virginia, Charlottesville, VA (United States); Wolf, Stuart A. [Univ. of Virginia, Charlottesville, VA (United States); Lukaszew, Rosa A. [College of William and Mary, Williamsburg, VA (United States)

    2014-01-01

    Upon a heating-induced metal–instulator transition (MIT) in VO{sub 2}, microscopic metallic VO{sub 2} puddles nucleate and coarsen within the insulating matrix. This coexistence of the two phases across the transition spans distinct length scales as their relative domain sizes change. Far-field optical probing is applied to follow the dynamic evolution of the highly correlated metallic domains as the MIT progresses.

  3. 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.

  4. 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.

  5. 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.

  6. The chemistry of transition metal complexes related to solar energy storage : H? production and small molecule (CO? and HX; X = Cl, Br) chemistry.

    E-Print Network [OSTI]

    Lee, Changhoon, Ph. D. Massachusetts Institute of Technology

    2011-01-01

    The studies in this thesis have focused on the chemistry of transition metal complexes related to solar energy storage: electrochemical H? production, HX splitting and CO? activation mediated by transition metal complexes. ...

  7. J. Phys. F: Met. Phys. 17 (1987)779-785. Printed in the UK Auger spectra of 3d transition metals with orbital degeneracy

    E-Print Network [OSTI]

    Presilla, Carlo

    1987-01-01

    J. Phys. F: Met. Phys. 17 (1987)779-785. Printed in the UK Auger spectra of 3d transition metals of Auger spectra of 3d transition metals and alloys (Weightman 1982). This large amount of work

  8. 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.

  9. ALLOYING-DRIVEN PHASE STABILITY IN GROUP-VB TRANSITION METALS UNDER COMPRESSION

    SciTech Connect (OSTI)

    Landa, A; Soderlind, P

    2011-04-11

    The change in phase stability of Group-VB (V, Nb, and Ta) transition metals due to pressure and alloying is explored by means of first-principles electronic-structure calculations. It is shown that under compression stabilization or destabilization of the ground-state body-centered cubic (bcc) phase of the metal is mainly dictated by the band-structure energy that correlates well with the position of the Kohn anomaly in the transverse acoustic phonon mode. The predicted position of the Kohn anomaly in V, Nb, and Ta is found to be in a good agreement with data from the inelastic x-ray or neutron scattering measurements. In the case of alloying the change in phase stability is defined by the interplay between the band-structure and Madelung energies. We show that band-structure effects determine phase stability when a particular Group-VB metal is alloyed with its nearest neighbors within the same d-transition series: the neighbor with less and more d electrons destabilize and stabilize the bcc phase, respectively. When V is alloyed with neighbors of a higher (4d- or 5d-) transition series, both electrostatic Madelung and band-structure energies stabilize the body-centered-cubic phase. The opposite effect (destabilization) happens when Nb or Ta is alloyed with neighbors of the 3d-transition series.

  10. Effect of edge roughness on electronic transport in graphene nanoribbon channel metal-oxide-semiconductor field-effect transistors

    E-Print Network [OSTI]

    Gilbert, Matthew

    Effect of edge roughness on electronic transport in graphene nanoribbon channel metal-oxide-semiconductor on transport in graphene nanoribbon metal-oxide-semiconductor field-effect transistors MOSFETs are reported of Physics. DOI: 10.1063/1.2839330 Graphene has recently generated considerable interest as a semiconductor

  11. 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.

  12. 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.

  13. Inorganic Metal Oxide/Organic Polymer Nanocomposites And Method Thereof

    DOE Patents [OSTI]

    Gash, Alexander E. (Livermore, CA); Satcher, Joe H. (Patterson, CA); Simpson, Randy (Livermore, CA)

    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.

  14. 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.

  15. Evaluation of Novel Ceria-Supported Metal Oxides As Oxygen Carriers for Chemical-Looping Combustion

    E-Print Network [OSTI]

    Azad, Abdul-Majeed

    for copper-based materials, and at 950 °C for iron- and manganese-based materials. Methane or syngas (50% COEvaluation of Novel Ceria-Supported Metal Oxides As Oxygen Carriers for Chemical-Looping Combustion of Chemical and Biological Engineering, Chalmers University of Technology, SE-412 96 Goteborg, Sweden

  16. A generalized kinetic model for the formation and growth of single-walled metal oxide nanotubes

    E-Print Network [OSTI]

    Nair, Sankar

    A generalized kinetic model for the formation and growth of single-walled metal oxide nanotubes G,n a School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA b School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA c

  17. Ternary Self-Assembly of Ordered Metal Oxide Graphene Nanocomposites for

    E-Print Network [OSTI]

    Aksay, Ilhan A.

    , or polymer-based nanocomposites.4,5,16,17 Recently, a range of nanoscale building blocks, including carbon to achieve similar control is to use amphiphilic polymer or surfactant to direct the self-assembly of nanostructured metal oxides, semiconductors, and polymer materials.11 15 There has been a growing in- terest

  18. 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.

  19. AC conductivity of nanoporous metal-oxide photoanodes for solar energy conversion

    E-Print Network [OSTI]

    Konezny, Steven J.

    AC conductivity of nanoporous metal-oxide photoanodes for solar energy conversion Steven J. Konezny% solar-to-electric energy conversion efficiency) exploited the large surface area of nanoporous thin for solar photoconversion is analyzed using a model based on fluctuation-induced tunneling conduction (FITC

  20. ANALYSIS OF THE ELECTRON EXCITATION SPECTRA IN HEAVY RARE EARTH METALS, HYDRIDES AND OXIDES

    E-Print Network [OSTI]

    Boyer, Edmond

    397 ANALYSIS OF THE ELECTRON EXCITATION SPECTRA IN HEAVY RARE EARTH METALS, HYDRIDES AND OXIDES C thin evaporated foils of heavy rare earths (Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) in three different chemical of high energy incident electrons (75 keV) transmitted through thin foils of yttric rare earth elements

  1. Transition Metal Carbonyl Complexes Inorganic Chemistry, Vol. 13,No. 6, 1974 1335 Contribution No. 2355 from the Department of Chemistry, Indiana University, Bloomington,Indiana 47401,

    E-Print Network [OSTI]

    Bodner, George M.

    Transition Metal Carbonyl Complexes Inorganic Chemistry, Vol. 13,No. 6, 1974 1335 Contribution No Magnetic Resonance Study of Transition Metal Carbonyl Complexes GEORGE M. BODNER* and LEE J. TODD Received on the arene ring may be explained in terms of changes in the extent of transition metal-, carbonyl R

  2. An ultrahigh vacuum facility for the co-deposition of amorphous transition metal alloy thin films 

    E-Print Network [OSTI]

    Nicoli, Victor Michael

    1984-01-01

    into the superconducting and electron transport properties of amorphous transition metal (TM) alloys is restricted primarily by the availability of high purity samples over a wide range of alloy concentrations. The goals of this thesis are to design components of..., and to assemble an ultrahigh vacuum (UHV) facility for the co-deposition of binary and ternary TN alloy metallic glasses which is also capable of in-situ characteriza- tion of a wide range of their properties in temperatures which vary from 1. 5 K to 300 K...

  3. 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.

  4. Nanoparticles as Reactive Precursors: Synthesis of Alloys, Intermetallic Compounds, and Multi-Metal Oxides Through Low-Temperature Annealing and Conversion Chemistry 

    E-Print Network [OSTI]

    Bauer, John C.

    2010-07-14

    and intermetallic compounds at or below 600 degrees C. This method was further extended to synthesizing multi-metal oxide systems by annealing metal oxide nanoparticle composites hundreds of degrees lower than more traditional methods. Nanoparticles of Pt (supported...

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. Magnetism of the rare earth, 3d --Theoretical review Abstract. --Compounds of rare earth and transition metals exhibit unusual and quite different behaviour. In

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    and secondly those determined mainly by rare earth metals. The first group are those rich in transition metal except TCo2, TNi5, T2Ni7, TNi3, TNi2. When the transition metal is magnetic, the coupling between rare-earth temperature are much smaller, and magnetic properties bear resemblances with rare earth metals. Thus we

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

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass map shines light on dark matter ByMentor-ProtegeFrom the Director HereMetal Current

  11. Catalysts for the selective oxidation of hydrogen sulfide to sulfur

    DOE Patents [OSTI]

    Srinivas, Girish (Thornton, CO); Bai, Chuansheng (Baton Rouge, LA)

    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.

  12. Rare earth zirconium oxide buffer layers on metal substrates

    DOE Patents [OSTI]

    Williams, Robert K. (Knoxville, TN); Paranthaman, Mariappan (Knoxville, TN); Chirayil, Thomas G. (Knoxville, TN); Lee, Dominic F. (Knoxville, TN); Goyal, Amit (Knoxville, TN); Feenstra, Roeland (Knoxville, TN)

    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.

  13. 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

  14. Theory of pressure-induced magnetic and metal-insulator transitions

    SciTech Connect (OSTI)

    Giesekus, A.; Falicov, L.M. (Department of Physics, University of California, Berkeley, California 94720 (United States) Materials Sciences Division, Lawrence Berkeley Laboratory, Berkeley, California 94720 (United States))

    1991-11-15

    A theory of pressure-induced simultaneous metal-insulator and magnetic phase transitions is presented. It is based on a model consisting of a periodic lattice with (1) an itinerant-electron band, (2) a narrow dispersionless band (localized states), (3) a hybridization term, (4) a very strong short-ranged repulsion between electrons of opposite spin in the localized states, and (5) a moderately strong short-ranged repulsion between electrons in the itinerant and localized bands. The problem is treated in the Hartree-Fock approximation, allowing spontaneous ferromagnetic broken symmetry. Pressure, which mainly changes the energy separation between the two bands, induces transitions from insulating, (ferro)magnetic states, to metallic states with no localized moments. The transition may be continuous or discontinuous, depending on the values of the interaction parameters. A richly structured phase diagram is obtained. For some values of the parameters the model reproduces in a reasonable fashion and for {ital T}{r arrow}0 the complex transition recently found in NiI{sub 2} at pressures of about 19 GPa.

  15. Color-control of the persistent luminescence of cadmium silicate doped with transition metals

    SciTech Connect (OSTI)

    Abreu, Carolina M., E-mail: carolabreu.fisica@gmail.com [Laboratory of Advanced Ceramics Materials, Physics Department, Federal University of Sergipe, 49100-000 São Cristóvão, SE (Brazil); Silva, Ronaldo S.; Valerio, Mário E.G.; Macedo, Zélia S. [Laboratory of Advanced Ceramics Materials, Physics Department, Federal University of Sergipe, 49100-000 São Cristóvão, SE (Brazil)

    2013-04-15

    The structural and optical characterization of cadmium silicate (CdSiO{sub 3}) doped with transition metals is reported. This crystalline system presents intrinsic luminescence and is usually studied as host matrix for rare earth ions. In this work, CdSiO{sub 3} was doped with Mn, Ni and Cr to produce multicolored luminescent materials. Single crystalline CdSiO{sub 3} was obtained via solid state synthesis at 1000 °C/8 h. The valence of the dopants inserted in the host matrix was determined via XANES as 3+ for Cr, 2+ for Ni and both 2+ and 3+ for Mn, according to XANES studies. The optical absorption spectra of the samples presented wide bands in the visible region that were associated with the internal transitions of the dopants. All the samples presented photoluminescent bands near 420 nm, 496 nm and 591 nm, with different relative intensities that yield characteristic luminescence colors ranging from blue to red. - Graphical abstract: Phosphorescence of cadmium silicate doped with transition metals: nature of defects and possible luminescent channels. Highlights: ? CdSiO{sub 3} was doped with Mn, Ni and Cr to produce multicolored phosphors. ? Valence of the dopants was determined as 3+ for Cr, 2+ for Ni and 2+ and 3+ for Mn. ? The presence of absorption bands in the visible region led to self-absorption. ? Self-absorption in some cases can decrease the light output. ? Luminescent channels were created and related to internal transitions of the dopants.

  16. Oxidation induced amorphous stabilization of the subsurface region in Zr-Cu metallic glass

    SciTech Connect (OSTI)

    Lim, K. R. [Light Metal Division, Korea Institute of Materials Science, 797 Changwondaero, Seongsan-gu, Changwon, Gyeongnam 642-831 (Korea, Republic of); Park, J. M. [Materials Research Center, Samsung Advanced Institute of Technology (SAIT) San 14-1, Nongseo-dong, Giheung-gu, Yongin-si, Gyeonggi-do 446-712 (Korea, Republic of); Park, S. H.; Na, M. Y.; Kim, K. C.; Kim, D. H., E-mail: dohkim@yonsei.ac.kr [Department of Materials Science and Engineering, Center for Non-crystalline Materials, Yonsei University, 134 Shinchon-dong, Seodaemun-gu, Seoul 120-749 (Korea, Republic of); Kim, W. T. [Department of Optical Engineering, Cheongju University, 36 Naedock-dong, Cheongju 360-764 (Korea, Republic of)

    2014-01-20

    In the present study, we demonstrate that selective surface oxidation of Zr{sub 70}Cu{sub 30} metallic glass can stabilize the amorphous structure in the subsurface region of the matrix. The oxidation proceeds by selective oxidation of Zr, forming monoclinic ZrO{sub 2} layer on the surface, and the subsurface layer becomes Cu-enriched due to back diffusion of Cu atoms from the oxide layer. Interestingly, in this system, the composition change in the subsurface region leads to enhancement of glass stability, forming of a double layered surface structure consisted of inner amorphous layer and outer monoclinic ZrO{sub 2} layer even when the remaining matrix is completely crystallized.

  17. 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 order–disorder 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.

  18. Variation of the density of states in amorphous GdSi at the metal-insulator transition 

    E-Print Network [OSTI]

    Bokacheva, L.; Teizer, Winfried; Hellman, F.; Dynes, RC.

    2004-01-01

    We have performed detailed conductivity and tunneling measurements on the amorphous, magnetically doped material alpha-GdxSi1-x, which can be driven through the metal-insulator transition by the application of an external magnetic field. Low...

  19. Dynamically Tracking the Strain Across the Metal-Insulator Transition in VO2 Measured Using Electromechanical Resonators

    E-Print Network [OSTI]

    Wu, Junqiao

    Electromechanical Resonators Pritesh Parikh,,, Chitraleema Chakraborty,, T. S. Abhilash, Shamashis Sengupta,*, Chun electromechanical device across the metal-insulator transition. Simultaneous resistance and resonance measurements strain coupled with simultaneous resistance and resonance measurements using electromechanical resonators

  20. 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.

  1. 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.

  2. 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.

  3. Modeling of surface oxidation and oxidation induced damage in metal matrix composites 

    E-Print Network [OSTI]

    Ma, Xinzheng

    1995-01-01

    of the moving interface problem. In addition to the surface oxidation formulation, a one-way coupled thermomechanical analysis of a unidirectional SiC/Ti-15-3 composite undergoing simple tension is performed and the critical applied load for surface crack...

  4. Metal-Insulator Transition Revisited for Cold Atoms in Non-Abelian Gauge Potentials

    E-Print Network [OSTI]

    Indubala I. Satija; Daniel C. Dakin; Charles W. Clark

    2006-07-10

    We discuss the possibility of realizing metal-insulator transitions with ultracold atoms in two-dimensional optical lattices in the presence of artificial gauge potentials. Such transitions have been extensively studied for magnetic fields corresponding to Abelian gauges; they occur when the magnetic flux penetrating the lattice plaquette is an irrational multiple of the magnetic flux quantum. Here we present the first study of these transitions for non-Abelian U(2) gauge fields, which can be realized with atoms with two pairs of degenerate internal states. In contrast to the Abelian case, the spectrum and localization transition in the non-Abelian case is strongly influenced by atomic momenta. In addition to determining the localization boundary, the momentum fragments the spectrum and the minimum energy viewed as a function of momentum exhibits a step structure. Other key characteristics of the non-Abelian case include the absence of localization for certain states and satellite fringes around the Bragg peaks in the momentum distribution and an interesting possibility that the transition can be tuned by the atomic momenta.

  5. The use of molecular dynamics for the thermodynamic properties of simple and transition metals

    SciTech Connect (OSTI)

    Straub, G.K.

    1987-04-01

    The technique of computer simulation of the molecular dynamics in metallic systems to calculate thermodynamic properties is discussed. The nature of a metal as determined by its electronic structure is used to determine the total adiabatic potential. The effective screened ion-ion interaction can then be used in a molecular dynamics simulation. The method for the construction of a molecular dynamics ensemble, its relation to the canonical ensemble, and the definition of thermodynamic functions from the Helmholtz free energy is given. The method for the analysis of the molecular dynamics results from quasiharmonic lattice dynamics and the decomposition in terms of harmonic and anharmonic contributions is given for solids. For fluid phase metals, procedures for calculating the thermodynamics and determining the constant of entropy are presented. The solid-fluid phase boundary as a function of pressure and temperature is determined using the results of molecular dynamics. Throughout, examples and results for metallic sodium are used. The treatment of the transition metal electronic d-states in terms of an effective pair-wise interaction is also discussed and the phonon dispersion curves of Al, Ni, and Cu are calculated.

  6. Inert anode containing oxides of nickel, iron and zinc useful for the electrolytic production of metals

    DOE Patents [OSTI]

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

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. Combinatorial approach for development of new metal oxides materials for all oxide photovoltaics

    E-Print Network [OSTI]

    Shimanovich, Klimentiy

    2015-01-01

    The combinatorial approach to all oxide material and device research is based on the synthesis of hundreds of related materials in a single experiment. This approach requires the development of new tools to rapidly characterize these materials libraries and new techniques to analyze the resulting data. The research presented here is intended to make a contribution towards meeting this demand, and thereby advance the pace of materials research. In many cases photovoltaic determinations are well-suited for high throughput methodologies, enabling direct quantitative analysis of properties whose implementation I demonstrate my thesis. This thesis focuses on the development and utilization of high throughput and combinatorial methods that have incorporated, or are associated with, the all-oxide photovoltaic field. The development of new absorbers often requires novel buffer layers, contact materials, and interface engineering. The importance and contribution of the combinatorial material science approach for the d...

  13. 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: zircon–monazite I–monazite 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.

  14. 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.

  15. 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.

  16. Effect of electron collecting metal oxide layer in normal and inverted structure polymer solar cells

    SciTech Connect (OSTI)

    Ng, A.; Liu, X.; Sun, Y. C.; Djuriši?, A. B. [Department of Physics, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. (China); Ng, A. M. C. [Department of Physics, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China and Nanostructure Institute for Energy and Environmental Research, Division of Physical Sciences, South University of Science and Technology of China, Shenzhen (China); Chan, W. K. [Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. (China)

    2013-12-04

    We performed a systematic study of the effect of electron collecting metal oxide layer on the performance of P3HT: PCBM solar cells. Zinc oxide (ZnO) or titanium dioxide (TiO{sub 2}) buffer layers were prepared by either e-beam evaporation or solution processing method. We also compared the photovoltaic performance of inserting the buffer layer between indium tin oxide (ITO) and the polymer layer for the inverted structure (ITO/ ZnO or TiO{sub 2}/P3HT:PCBM/V{sub 2}O{sub 5}/Au) as well as inserting the buffers layers between the polymer and the aluminum electrode for the conventional structure (ITO/V{sub 2}O{sub 5}/P3HT:PCBM/ZnO or TiO{sub 2}/Al). The results are shown in detail.

  17. 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.

  18. Modelling of thermo-mechanical and irradiation behavior of metallic and oxide fuels for sodium fast reactors

    E-Print Network [OSTI]

    Karahan, Aydin

    2009-01-01

    A robust and reliable code to model the irradiation behavior of metal and oxide fuels in sodium cooled fast reactors is developed. Modeling capability was enhanced by adopting a non-empirical mechanistic approach to the ...

  19. 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].

  20. Interplay between Ferroelastic and Metal-Insulator Phase Transitions in Strained Quasi-2D VO[subscript 2] Nanoplatelets

    SciTech Connect (OSTI)

    Tselev, Alexander; Strelcov, Evgheni; Luk’ yanchuk, Igor A.; Budai, John D.; Tischler, Jonathan Z.; Ivanov, Ilia N.; Jones, Keith; Proksch, Roger; Kalinin, Sergei V.; Kolmakov, Andrei (Asylum); (ORNL); (SIUC); (UPJV)

    2011-08-09

    Formation of ferroelastic twin domains in vanadium dioxide (VO{sub 2}) nanosystems can strongly affect local strain distributions, and hence couple to the strain-controlled metal-insulator transition. Here we report polarized-light optical and scanning microwave microscopy studies of interrelated ferroelastic and metal-insulator transitions in single-crystalline VO{sub 2} quasi-two-dimensional (quasi-2D) nanoplatelets (NPls). In contrast to quasi-1D single-crystalline nanobeams, the 2D geometric frustration results in emergence of several possible families of ferroelastic domains in NPls, thus allowing systematic studies of strain-controlled transitions in the presence of geometrical frustration. We demonstrate the possibility of controlling the ferroelastic domain population by the strength of the NPl-substrate interaction, mechanical stress, and by the NPl lateral size. Ferroelastic domain species and domain walls are identified based on standard group-theoretical considerations. Using variable temperature microscopy, we imaged the development of domains of metallic and semiconducting phases during the metal-insulator phase transition and nontrivial strain-driven reentrant domain formation. A long-range reconstruction of ferroelastic structures accommodating metal-insulator domain formation has been observed. These studies illustrate that a complete picture of the phase transitions in single-crystalline and disordered VO{sub 2} structures can be drawn only if both ferroelastic and metal-insulator strain effects are taken into consideration and understood.

  1. 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)

  2. 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.

  3. 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.

  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. 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...

  6. Electrocatalytic Measurement Methodology of Oxide Catalysts Using a Thin-Film Rotating Disk Electrode

    E-Print Network [OSTI]

    Suntivich, Jin

    Transition-metal oxides can exhibit high electrocatalytic activity for reactions such as the oxygen reduction reaction (ORR) in alkaline media. It is often difficult to measure and compare the activities of oxide catalysts ...

  7. Hydrocarbon reaction with HF-cleaned Si(lOQ) and effects on metal-oxide-semiconductor device quality

    E-Print Network [OSTI]

    Rubloff, Gary W.

    Hydrocarbon reaction with HF-cleaned Si(lOQ) and effects on metal-oxide-semiconductor device-cleaned Si( 100) towards hydrocarbon adsorption is examined by surface analysis; most hydrocarbons adsorb oxidation after HF treatment.4'5 In this letter, passivation against hydrocarbon contamination is studied

  8. Gas Carburization of Thin-Walled Austenitic Stainless Steel Formed via the Reduction of Metal Oxide Extrusions

    E-Print Network [OSTI]

    Li, Mo

    Gas Carburization of Thin-Walled Austenitic Stainless Steel Formed via the Reduction of Metal Oxide with constant carbon composition. In the case of stainless steels, the protective layer of chrome oxide must the surface hardness of steel by introducing a carbon-rich gas environment to a specimen at an elevated

  9. Beryllium Adsorption at Transition Aluminas: Implications for Environmental Science and Oxidation of Aluminum Alloys

    SciTech Connect (OSTI)

    Sergey N. Rashkeev; Michael V. Glazoff

    2010-08-01

    It is demonstrated that?gamma- and?eta- aluminas (transition Al2O3 polytypes with defect spinel structure) can effectively capture beryllium atoms. Although the bulk crystal structures of these two oxides are characterized only by slight differences in cation vacancy distributions, the interaction of Be with the two polytypes are different. For gamma- Al2O3, the Be adsorption energy is high (~ 5 eV per atom), and all Be atoms are captured and trapped at the surface - all attempts to move Be in the subsurface region result in its expulsion back to the surface. On the other hand, for ?eta- alumina Be atoms can be captured both at the surface and in octahedrally-coordinated subsurface cation vacancies. This result implies that both alumina oxides could be successfully used for Be capture out of wastewater streams related to industrial processes of aluminum and alumina production. Also, the surface adsorption mechanism of Be at?gamma- Al2O3 explains why very small additions of Be (of the order of several ppm) to Al-Mg and Al-Mg-Si casting and wrought alloys prevent run-away oxidation of these materials in molten state, as well as ingot cracking. We also discuss possibilities to use other additives (e.g., Ca and Sr) yielding the same protective effect for aluminum alloys but which are less toxic than beryllium.

  10. 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].

  11. Electronic Structure of Transition Metal Clusters, Actinide Complexes and Their Reactivities

    SciTech Connect (OSTI)

    Krishnan Balasubramanian

    2009-07-18

    This is a continuing DOE-BES funded project on transition metal and actinide containing species, aimed at the electronic structure and spectroscopy of transition metal and actinide containing species. While a long term connection of these species is to catalysis and environmental management of high-level nuclear wastes, the immediate relevance is directly to other DOE-BES funded experimental projects at DOE-National labs and universities. There are a number of ongoing gas-phase spectroscopic studies of these species at various places, and our computational work has been inspired by these experimental studies and we have also inspired other experimental and theoretical studies. Thus our studies have varied from spectroscopy of diatomic transition metal carbides to large complexes containing transition metals, and actinide complexes that are critical to the environment. In addition, we are continuing to make code enhancements and modernization of ALCHEMY II set of codes and its interface with relativistic configuration interaction (RCI). At present these codes can carry out multi-reference computations that included up to 60 million configurations and multiple states from each such CI expansion. ALCHEMY II codes have been modernized and converted to a variety of platforms such as Windows XP, and Linux. We have revamped the symbolic CI code to automate the MRSDCI technique so that the references are automatically chosen with a given cutoff from the CASSCF and thus we are doing accurate MRSDCI computations with 10,000 or larger reference space of configurations. The RCI code can also handle a large number of reference configurations, which include up to 10,000 reference configurations. Another major progress is in routinely including larger basis sets up to 5g functions in thee computations. Of course higher angular momenta functions can also be handled using Gaussian and other codes with other methods such as DFT, MP2, CCSD(T), etc. We have also calibrated our RECP methods with all-electron Douglas-Kroll relativistic methods. We have the capabilities for computing full CI extrapolations including spin-orbit effects and several one-electron properties and electron density maps including spin-orbit effects. We are continuously collaborating with several experimental groups around the country and at National Labs to carry out computational studies on the DOE-BES funded projects. The past work in the last 3 years was primarily motivated and driven by the concurrent or recent experimental studies on these systems. We were thus significantly benefited by coordinating our computational efforts with experimental studies. The interaction between theory and experiment has resulted in some unique and exciting opportunities. For example, for the very first time ever, the upper spin-orbit component of a heavy trimer such as Au{sub 3} was experimentally observed as a result of our accurate computational study on the upper electronic states of gold trimer. Likewise for the first time AuH{sub 2} could be observed and interpreted clearly due to our computed potential energy surfaces that revealed the existence of a large barrier to convert the isolated AuH{sub 2} back to Au and H{sub 2}. We have also worked on yet to be observed systems and have made predictions for future experiments. We have computed the spectroscopic and thermodynamic properties of transition metal carbides transition metal clusters and compared our electronic states to the anion photodetachment spectra of Lai Sheng Wang. Prof Mike Morse and coworkers(funded also by DOE-BES) and Prof Stimle and coworkers(also funded by DOE-BES) are working on the spectroscopic properties of transition metal carbides and nitrides. Our predictions on the excited states of transition metal clusters such as Hf{sub 3}, Nb{sub 2}{sup +} etc., have been confirmed experimentally by Prof. Lombardi and coworkers using resonance Raman spectroscopy. We have also been studying larger complexes critical to the environmental management of high-level nuclear wastes. In collaboration with experimental co

  12. 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.

  13. 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 800°C. The 15Pd system exhibits a lower ambient temperature strength that is retained at 800°C. 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.

  14. 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).

  15. ELM Control at the L-H Transition Achieved by Pellet Pacing in the All-metal Wall Tokamaks ASDEX Upgrade and JET

    E-Print Network [OSTI]

    ELM Control at the L-H Transition Achieved by Pellet Pacing in the All-metal Wall Tokamaks ASDEX Upgrade and JET

  16. Low temperature photochemical vapor deposition of alloy and mixed metal oxide films

    DOE Patents [OSTI]

    Liu, David K. (San Pablo, CA)

    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.

  17. 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.

  18. 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.

  19. 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.

  20. The behavior of a solid oxide fuel cell (SOFC) cermet (ceramic-metal composite) anode under reaction conditions depends significantly on the structure, morphology and atomic scale interactions between the metal and the ceramic

    E-Print Network [OSTI]

    The behavior of a solid oxide fuel cell (SOFC) cermet (ceramic-metal composite) anode under for Solid Oxide Fuel Cell Anodes Vaneet Sharma Advisors: Peter A. Crozier and Renu Sharma November 3, 2011

  1. 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.

  2. Characterization of a Fe/Y[subscript 2]O[subscript 3] metal/oxide interface using neutron and x-ray scattering

    E-Print Network [OSTI]

    Watkins, E. B.

    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[subscript ...

  3. 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.

  4. 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.

  5. 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.

  6. Water growth on metals and oxides: binding, dissociation and role of hydroxyl groups

    SciTech Connect (OSTI)

    Salmeron, M.; Bluhm, H.; Tatarkhanov, M.; Ketteler, G.; Shimizu, T.K.; Mugarza, A.; Deng, Xingyi; Herranz, T.; Yamamoto, S.; Nilsson, A.

    2008-09-01

    The authors discuss the role of the presence of dangling H bonds from water or from surface hydroxyl species on the wetting behavior of surfaces. Using Scanning Tunneling and Atomic Force Microscopies, and Photoelectron Spectroscopy, they have examined a variety of surfaces, including mica, oxides, and pure metals. They find that in all cases, the availability of free, dangling H-bonds at the surface is crucial for the subsequent growth of wetting water films. In the case of mica electrostatic forces and H-bonding to surface O atoms determine the water orientation in the first layer and also in subsequent layers with a strong influence in its wetting characteristics. In the case of oxides like TiO{sub 2}, Cu{sub 2}O, SiO{sub 2} and Al{sub 2}O{sub 3}, surface hydroxyls form readily on defects upon exposure to water vapor and help nucleate the subsequent growth of molecular water films. On pure metals, such as Pt, Pd, and Ru, the structure of the first water layer and whether or not it exhibits dangling H bonds is again crucial. Dangling H-bonds are provided by molecules with their plane oriented vertically, or by OH groups formed by the partial dissociation of water. By tying the two II atoms of the water molecules into strong H-bonds with pre-adsorbed O on Ru can also quench the wettability of the surface.

  7. 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.

  8. 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.

  9. Mechanical properties, glass transition temperature, and bond enthalpy trends of high metalloid Fe-based bulk metallic glasses

    E-Print Network [OSTI]

    Widom, Michael

    Mechanical properties, glass transition temperature, and bond enthalpy trends of high metalloid Fe December 2007; accepted 8 April 2008; published online 25 April 2008 Mechanical properties and glass plastic strain of 3% is obtained, despite the increase in the number of strong metal-metalloid bonds. Also

  10. A new local density functional for main-group thermochemistry, transition metal bonding, thermochemical kinetics, and noncovalent interactions

    E-Print Network [OSTI]

    Truhlar, Donald G

    A new local density functional for main-group thermochemistry, transition metal bonding online 15 November 2006 We present a new local density functional, called M06-L, for main is designed to capture the main dependence of the exchange-correlation energy on local spin density, spin

  11. Linear temperature dependence of the conductivity in Si two-dimensional electrons near the apparent metal-to-insulator transition

    E-Print Network [OSTI]

    Dobrosavljevic, Vladimir

    Linear temperature dependence of the conductivity in Si two-dimensional electrons near the apparent mobility two-dimensional electron system in Si, near the critical density, nc=0.32 1011 cm-2 , of the apparent metal-to-insulator transition, the conductivity displays a linear temperature T dependence around

  12. Strain and electric field induced electronic properties of two-dimensional hybrid bilayers of transition-metal dichalcogenides

    E-Print Network [OSTI]

    Pandey, Ravi

    . VC 2014 AIP Publishing LLC. [http://dx.doi.org/10.1063/1.4892798] I. INTRODUCTION Two dimensional (2D the semiconductor-to-metal transition. Application of the external electric fields, on the other hand, shows- liation technique similar to one applied to graphene. The layered TMDs are the class of materials

  13. Journal of Crystal Growth 287 (2006) 402407 Transition metals in photovoltaic-grade ingot-cast multicrystalline

    E-Print Network [OSTI]

    2006-01-01

    Journal of Crystal Growth 287 (2006) 402­407 Transition metals in photovoltaic-grade ingot-cast silicon (mc-Si) ingot casting for cost-effective solar cell wafer production. Highly sensitive to coat the inside of mc-Si ingot-casting crucibles, as well as the as-grown cast mc-Si material

  14. Method and apparatus for preparation of spherical metal carbonates and lithium metal oxides for lithium rechargeable batteries

    DOE Patents [OSTI]

    Kang, Sun-Ho (Naperville, IL); Amine, Khalil (Downers Grove, IL)

    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.

  15. 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

  16. Kinetic Consequences of Chemisorbed Oxygen Atoms during Methane Oxidation on Group VIII Metal Clusters

    E-Print Network [OSTI]

    Chin, Ya Huei

    2011-01-01

    Chin, Y-H. ; Resasco, D.E. Catalytic Oxidation of methane onreactions in catalytic partial oxidation, reforming, andoccurrence of direct catalytic partial oxidation of methane

  17. Hydrogenation of CO2 to methanol: Importance of metal–oxide and metal–carbide interfaces in the activation of CO2

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

    Rodriguez, José A.; Liu, Ping; Stacchiola, Dario J.; Senanayake, Sanjaya D.; White, Michael G.; Chen, Jingguang G.

    2015-09-30

    In this study, the high thermochemical stability of CO2 makes it very difficult to achieve the catalytic conversion of the molecule into alcohols or other hydrocarbon compounds, which can be used as fuels or the starting point for the generation of fine chemicals. Pure metals and bimetallic systems used for the CO2 ? CH3OH conversion usually bind CO2 too weakly and, thus, show low catalytic activity. Here, we discuss a series of recent studies that illustrate the advantages of metal–oxide and metal–carbide interfaces when aiming at the conversion of CO2 into methanol. CeOx/Cu(111), Cu/CeOx/TiO2(110), and Au/CeOx/TiO2(110) exhibit an activity formore »the CO2 ? CH3OH conversion that is 2–3 orders of magnitude higher than that of a benchmark Cu(111) catalyst. In the Cu–ceria and Au–ceria interfaces, the multifunctional combination of metal and oxide centers leads to complementary chemical properties that open active reaction pathways for methanol synthesis. Efficient catalysts are also generated after depositing Cu and Au on TiC(001). In these cases, strong metal–support interactions modify the electronic properties of the admetals and make them active for the binding of CO2 and its subsequent transformation into CH3OH at the metal–carbide interfaces.« less

  18. 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.

  19. 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.

  20. Porphyrins and metal complexes thereof having haloalkyl side chains

    DOE Patents [OSTI]

    Wijesekera, Tilak (Glen Mills, PA); Lyons, James E. (Wallingford, PA); Ellis, Jr., Paul E. (Downingtown, PA); Bhinde, Manoj V. (Boothwyn, PA)

    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.

  1. 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.

  2. Method for producing metal oxide aerogels having densities less than 0.02 g/cc

    SciTech Connect (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.

  3. 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.

  4. 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.

  5. Dilute magnetic semiconductor and half-metal behaviour mediated by 3d transition-metal doped in black/blue phosphorene

    E-Print Network [OSTI]

    Yu, Weiyang; Niu, Chun-Yao; Li, Chong; Cho, Jun-Hyung; Jia, Yu

    2015-01-01

    Using first-principles calculations, we present a theoretical study of the structural, electronic and magnetic properties of 3d transition metal (TM) atoms interacting with phosphorus monovacancies in two-dimensional black/blue phosphorene. We pay special attention to the magnetic properties of these substitutional impurities and find that they can be fully understood by a simple model based on the Hund's rule. For TM-doped black phosphorene, the calculated band structures of substitutional Ti, Cr, Mn, Fe and Ni impurities show dilute magnetic semiconductor (DMS) properties while those of substitutional Sc, V and Co impurities show nonmagnetic property. For TM-doped blue phosphorene, the calculated band structures of substitutional V, Cr, Mn and Fe impurities show DMS properties, and those of substitutional Ti and Ni impurities show half-metal properties, while Sc and V impurities show nonmagnetic property. We identify three different regimes associated with the occupation of different phosphorus-metal hybrid...

  6. Process for improving metal production in steelmaking processes

    SciTech Connect (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.

  7. 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.

  8. Hydrocracking of n-decane over zeolite-supported metal sulfide catalysts. 1: CaY-supported transition metal sulfides

    SciTech Connect (OSTI)

    Welters, W.J.J.; Waerden, O.H. van der; Beer, V.H.J. de; Santen, R.A. van [Eindhoven Univ. of Technology (Netherlands). Schuit Inst. of Catalysis; Zandbergen, H.W. [Delft Univ. of Technology (Netherlands). Centre for High Resolution Electron Microscopy

    1995-04-01

    The hydrocracking properties of various CaY-supported metal (Fe, Co, Ni, Mo, Ru, Rh, Pd, W, Re, Ir, and Pt) sulfide catalysts (prepared by impregnation) are examined by studying the hydroconversion of n-decane. All catalysts show cracking conversions which are significantly higher than that of the CaY support. There are large differences in catalytic behavior dependent on the metal sulfide present on the zeolite support. The amounts of S present on the catalyst are analyzed to determine the degree of sulfidation of the metal sulfide, while high resolution electron microscopy is used to characterize the distribution of the metal sulfide phase over the zeolite support. The observed differences in activity can be explained by the differences in intrinsic activity of the metal sulfide phase and the differences in distribution of this phase over the zeolite particle (internal or external sulfide deposition).

  9. Microstructure of cosputter-deposited metal-and oxide-MoS2 solid lubricant thin films

    E-Print Network [OSTI]

    Marks, Laurence D.

    Microstructure of cosputter-deposited metal- and oxide-MoS2 solid lubricant thin films M. R of cosputtering small amounts of Ni (3%, 9%) and SbOx (20%) on the final microstructure of MoS2 lubricant thin performance is discussed. I. INTRODUCTION Sputter-deposited films of MoS2 have been used as solid lubricants

  10. Mechanisms of poron Adsorption on Metal Oxides. C.V. TONER, IV and D.l. SPARKS, Univ. of Delaware.

    E-Print Network [OSTI]

    Sparks, Donald L.

    Mechanisms of poron Adsorption on Metal Oxides. C.V. TONER, IV· and D.l. SPARKS, Univ. of Delaware in the soil solution. Yet the reaction mechanism has not been firmly established. Pressure-jump relaxation kjnetic experiments were conducted to determine the mechanism ,of borate adsorption on alUlllina (1 Al~03

  11. Devices and chemical sensing applications of metal oxide nanowires Guozhen Shen,* Po-Chiang Chen, Koungmin Ryu and Chongwu Zhou*

    E-Print Network [OSTI]

    Zhou, Chongwu

    . Finally, we will conclude this review with some perspectives and outlook on the future developments, nanogenerators, solar cells and photo- catalysts, and field nanoemitters. In the third part, we will discuss with some perspectives and outlook on the future developments in the metal oxide nanowire research area. 2

  12. Real-Time Observation of Atomic Layer Deposition Inhibition: Metal Oxide Growth on Self-Assembled Alkanethiols

    E-Print Network [OSTI]

    Real-Time Observation of Atomic Layer Deposition Inhibition: Metal Oxide Growth on Self each atomic layer deposition (ALD) cycle to an analytical island-growth model that enables moderately optimized conditions. KEYWORDS: atomic layer deposition, self-assembled monolayers, quartz crystal

  13. 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.

  14. 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.

  15. INFLUENCE OF OXIDE GROWTH AND METAL CREEP ON STRAIN DEVELOPMENT IN THE STEAM-SIDE OXIDE IN BOILER TUBES

    SciTech Connect (OSTI)

    Sabau, Adrian S [ORNL; Wright, Ian G [ORNL

    2010-01-01

    This effort is concerned with developing a quantitative description of the exfoliation behavior of oxide scales grown inside steam tubes in a pressure boiler. Consideration of the development of stress/strain in growing oxides has included expansion mismatch-induced strains during thermal cycling as well as inelastic mechanical effects from oxide/alloy creep phenomena and volume change from oxide growth. The magnitude of the parameters used has been closely matched to actual boiler operating practice. The creep model used was validated against published data. Representation of oxide growth-induced strain was found to be a difficult challenge because the processes involved are not fully understood. In addition to the traditional uniaxial (radial) and dilatational models, lateral growth models are discussed in the context of experimentally-derived criteria, such as the level of elastic strains involved in oxide exfoliation. It was found that strain variation in the oxide cannot be neglected.

  16. Laminar and transitional liquid metal duct flow near a magnetic point dipole

    E-Print Network [OSTI]

    Tympel, Saskia; Schumacher, Jörg

    2013-01-01

    The flow transformation and the generation of vortex structures by a strong magnetic dipole field in a liquid metal duct flow is studied by means of three-dimensional direct numerical simulations. The dipole is considered as the paradigm for a magnetic obstacle which will deviate the streamlines due to Lorentz forces acting on the fluid elements. The duct is of square cross-section. The dipole is located above the top wall and is centered in spanwise direction. Our model uses the quasi-static approximation which is applicable in the limit of small magnetic Reynolds numbers. The analysis covers the stationary flow regime at small hydrodynamic Reynolds numbers $Re$ as well as the transitional time-dependent regime at higher values which may generate a turbulent flow in the wake of the magnetic obstacle. We present a systematic study of these two basic flow regimes and their dependence on $Re$ and on the Hartmann number $Ha$, a measure of the strength of the magnetic dipole field. Furthermore, three orientations...

  17. Tunnel Field-Effect Transistors in 2D Transition Metal Dichalcogenide Materials

    E-Print Network [OSTI]

    Ilatikhameneh, Hesameddin; Novakovic, Bozidar; Klimeck, Gerhard; Rahman, Rajib; Appenzeller, Joerg

    2015-01-01

    In this work, the performance of Tunnel Field-Effect Transistors (TFETs) based on two-dimensional Transition Metal Dichalcogenide (TMD) materials is investigated by atomistic quantum transport simulations. One of the major challenges of TFETs is their low ON-currents. 2D material based TFETs can have tight gate control and high electric fields at the tunnel junction, and can in principle generate high ON-currents along with a sub-threshold swing smaller than 60 mV/dec. Our simulations reveal that high performance TMD TFETs, not only require good gate control, but also rely on the choice of the right channel material with optimum band gap, effective mass and source/drain doping level. Unlike previous works, a full band atomistic tight binding method is used self-consistently with 3D Poisson equation to simulate ballistic quantum transport in these devices. The effect of the choice of TMD material on the performance of the device and its transfer characteristics are discussed. Moreover, the criteria for high ON...

  18. 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.

  19. Durability study of transition metal based non-precious cathode in PEFC

    SciTech Connect (OSTI)

    Wu, Gang [Los Alamos National Laboratory; Zelenay, Piotr [Los Alamos National Laboratory

    2009-01-01

    This paper focuses on performance durability of newly developed polyaniline (PANI)-derived non-precious cathode catalyst, whose high oxygen-reduction activity was verified in electrochemical and fuel cell testing, exhibiting onset and half-wave potential (E{sup 1/2}) of oxygen reduction at 0.90 V and 0.77 V, respectively, as well as an insignificant H{sub 2}O{sub 2} yields below 1%. It was found catalyst durability in fuel cell life tests is greatly dependent on the catalyst synthesis including nitrogen precursors, employed transition metals, and supporting materials. Importantly, the working voltages in fuel cell testing have a profound impact on the stability, which much more stable performance can be observed at lower voltage such as 0.4 V when compared with higher voltage, 0.6 V. Preliminary physical and electrochemical characterization present to provide insight into the origin of the possible degradation mechanism for the non-precious active sites.

  20. 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.

  1. 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.

  2. 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?O·H?O 2, have been synthesized via the hydrothermal technique and characterized by single crystal X-ray diffraction analyses, IR, XPS, TG analysis, UV–DRS, 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)?]²? 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 0–50 mT in the range of 600–1000 cm?¹, 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.

  3. Alloy Films Deposited by Electroplating as Precursors for Protective Oxide Coatings on Solid Oxide Fuel Cells Metallic Interconnect Materials

    SciTech Connect (OSTI)

    Johnson, Christopher; Gemmen, R.S.; Cross, Caleb

    2006-10-01

    The successful development of stainless steel interconnects for intermediate temperature solid oxide fuel cells (SOFC) may be the materials breakthrough that makes SOFC technology truly commercial. Many of the ferritic stainless steels, however, suffer from a relatively high area specific resistance (ASR) after long exposure times at temperature and the Cr in the native oxide can evaporate and contaminate other cell components. Conductive coatings that resist oxide scale growth and chromium evaporation may prevent both of these problems. In the present study electrochemical deposition of binary alloys followed by oxidation of the alloy to form protective and conductive oxide layers is examined. Results are presented for the deposition of Mn/Co and Fe/Ni alloys via electroplating to form a precursor for spinel oxide coating formation. Analysis of the alloy coatings is done by SEM, EDS and XRD.

  4. Influence of transition metals on the surface acidic properties of titania prepared by sol-gel route

    SciTech Connect (OSTI)

    Shali, N.B. [Department of Applied Chemistry, Cochin University of Science and Technology, Cochin-22, Kerala (India); Sugunan, S. [Department of Applied Chemistry, Cochin University of Science and Technology, Cochin-22, Kerala (India)]. E-mail: ssg@cusat.ac.in

    2007-09-04

    A series of titania catalysts containing chromium, molybdenum as well as tungsten has been prepared by colloidal sol-gel route using metatitanic acid as the precursor. Structural characterization of the prepared catalysts was done with Energy dispersive X-ray analysis, X-ray diffraction, BET surface area and pore volume measurements. The influence of different transition metals like chromium, molybdenum and tungsten on the surface acidic properties of titania is investigated in detail. Two independent methods have been used to study the surface acidity of these catalyst systems: temperature programmed desorption of ammonia which is a measure of total acidity and thermodesorption studies using 2,6-dimethyl pyridine which is a measure of Bronsted acidity. Cumene cracking reaction is carried out over the prepared systems for further characterizing the acidity of the prepared catalysts. Remarkable enhancement in the surface acidity is observed after transition metal incorporation. The catalytic activity of the prepared catalysts was tested towards the dehydrogenation of cyclohexane.

  5. FINAL TECHNICAL REPORT Synthetic, Structural and Mechanistic Investigations of Olefin Polymerization Catalyzed by Early Transition Metal Compounds

    SciTech Connect (OSTI)

    Bercaw, John E. [California Institute of Technology

    2014-05-23

    The goal of this project is to develop new catalysts and provide understanding of ligand effects on catalyst composition in order to guide development of superior catalyst systems for polymerization of olefins. Our group is designing and synthesizing new “LX2”,“pincer” type ligands and complexing early transition metals to afford precatalysts. In a collaboration with Hans Brintzinger from the University of Konstanz, we are also examining the structures of the components of catalyst systems obtained from reaction of zirconocene dichlorides with aluminum alkyls and aluminum hydrides. Such systems are currently used commercially to produce polyolefins, but the nature of the active and dormant species as well as the mechanisms of their interconversions are not understood. New information on catalyst design and performance may lead to new types of polymers and/or new chemical transformations between hydrocarbons and transition metal centers, ultimately contributing to the development of catalytic reactions for the production of fuels, commodity and polymeric materials.

  6. Nitric oxide protects the heart from ischemia-induced apoptosis and mitochondrial damage via protein kinase G mediated blockage of permeability transition and cytochrome c release

    E-Print Network [OSTI]

    Borutaite, Vilmante; Morkuniene, Ramune; Arandarcikaite, Odeta; Jekabsone, Aiste; Barauskaite, Jurgita; Brown, Guy C.

    2009-08-11

    Abstract Background Heart ischemia can rapidly induce apoptosis and mitochondrial dysfunction via mitochondrial permeability transition-induced cytochrome c release. We tested whether nitric oxide (NO) can block this damage in isolated rat heart...

  7. 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.

  8. 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.

  9. 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.

  10. Soluble transition metals cause the pro-inflammatory effects of welding fumes in vitro 

    E-Print Network [OSTI]

    McNeilly, Jane D; Heal, Mathew R; Beverland, Iain J; Howe, Alan; Gibson, Mark D; Hibbs, Leon; MacNee, William; Donaldson, Ken

    2004-01-01

    Epidemiological studies have consistently reported a higher incidence of respiratory illnesses such as bronchitis, metal fume fever (MFF), and chronic pneumonitis among welders exposed to high concentrations of metal-enriched ...

  11. Rapid low-temperature processing of metal-oxide thin film transistors with combined far ultraviolet and thermal annealing

    SciTech Connect (OSTI)

    Leppäniemi, J. Ojanperä, 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}/(V·s). 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}/(V·s) and 7.5?cm{sup 2}/(V·s), 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.

  12. The pure rotational spectrum of TiF,,X4 r...: 3d transition metal

    E-Print Network [OSTI]

    Ziurys, Lucy M.

    corrosion resistance, the metal and its alloys are used in the construction of aircraft and marine vehicle

  13. 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).

  14. 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).

  15. 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.

  16. Ultra-stable Molecule-Surface Architectures at Metal Oxides: Structure, Bonding, and Electron-transfer Processes

    SciTech Connect (OSTI)

    Hamers, Robert John

    2013-12-07

    Research funded by this project focused on the development of improved strategies for functionalization of metal oxides to enhance charge?transfer processes relevant to solar energy conversion. Initial studies included Fe2O3, WO3, TiO2, SnO2, and ZnO as model oxide systems; these systems were chosen due to differences in metal oxidation state and chemical bonding types in these oxides. Later studies focused largely on SnO2 and ZnO, as these materials show particularly promising surface chemistry, have high electron mobility, and can be readily grown in both spherical nanoparticles and as elongated nanorods. New molecules were synthesized that allowed the direct chemical assembly of novel nanoparticle ?dyadic? structures in which two different oxide materials are chemically joined, leading to an interface that enhances the separation of of charge upon illumination. We demonstrated that such junctions enhance photocatalytic efficiency using model organic compounds. A separate effort focused on novel approaches to linking dye molecules to SnO2 and ZnO as a way to enhance solar conversion efficiency. A novel type of surface binding through

  17. Spectroscopy of jet-cooled AlMn and trends in the electronic structure of the 3d transition metal aluminides

    E-Print Network [OSTI]

    Morse, Michael D.

    Spectroscopy of jet-cooled AlMn and trends in the electronic structure of the 3d transition metal, Utah 84112 (Received 9 May 1994; accepted 28 June 1994) Jet-cooled diatomic AlMn has been

  18. 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...

  19. Templated Assembly of Metal-Anion Arrays within Layered Hosts; Synthesis and Characterization of New Transition-Metal Oxyhalide Perovskites

    E-Print Network [OSTI]

    Spinu, Leonard

    form a distinct class of inorganic materials whose structure is conventionally described as intergrowthTemplated Assembly of Metal-Anion Arrays within Layered Hosts; Synthesis and Characterization, and John B. Wiley* Department of Chemistry and the Advanced Materials Research Institute, University of New

  20. 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.

  1. SURFACE DAMAGE OF OXIDIZED METAL MATRIX COMPOSITE LAMINATES UNDER TRANSVERSE TENSION

    E-Print Network [OSTI]

    of surface cracks in the oxide layer is assumed. The critical value of the applied mechanical load, which the oxide layer, caused by the diffusion of oxygen, on the stress field is considered. 1. INTRODUCTION a brittle oxide layer on the titanium alloy develops. This oxide layer initiates and accelerates damage

  2. 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.

  3. Communications to the Editor A General Mechanism for CO Oxidation on

    E-Print Network [OSTI]

    Alavi, Ali

    Communications to the Editor A General Mechanism for CO Oxidation on Close-Packed Transition Metal, U.K. ReceiVed May 5, 1999 ReVised Manuscript ReceiVed June 28, 1999 CO oxidation on metal surfaces is one of the most important catalytic reactions due primarily to two reasons.1-3 Technologi- cally

  4. 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.

  5. 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.

  6. 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.

  7. 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 (800-1000°C) 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 ºC to ~750 ºC 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.

  8. 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.

  9. Identifying the Role of N-Heteroatom Location in the Activity of Metal Catalysts for Alcohol Oxidation

    SciTech Connect (OSTI)

    Chan-Thaw, Carine E. [Universita di Milano, Italy; Veith, Gabriel M [ORNL; Villa, Alberto [Universita di Milano, Italy; Prati, Laura [Universita di Milano, Italy

    2015-01-01

    This work focuses on understanding how the bonding of nitrogen heteroatoms contained on/in a activated carbon support influence the stability and reactivity of a supported Pd catalyst for the oxidation of alcohols in solution. The results show that simply adding N groups via solution chemistry is insufficient to improve catalytic properties. Instead a strongly bound N moiety is required to activate the catalyst and stabilize the metal particles.

  10. Improved layered mixed transition metal oxides for Li-ion batteries

    E-Print Network [OSTI]

    Doeff, Marca M.

    2010-01-01

    for rechargeable lithium batteries," Science 311(5763), 977-^ for Advanced Lithium-Ion Batteries," J. Electrochem. Soc.02 for lithium-ion batteries," Chem. Lett. , [3] Yabuuchi,

  11. Finding Room for Improvement in Transition Metal Oxides Cathodes for Lithium-ion Batteries

    E-Print Network [OSTI]

    Kam, Kinson

    2012-01-01

    Cathodes for Lithium-ion Batteries Kinson C. Kam and Marcarechargeable lithium-ion batteries has become an integral

  12. Transition Metal Oxide Nanoparticles Anchored Nanocarbon Hybrid Foam for High Performance Electrochemical Energy Storage Applications

    E-Print Network [OSTI]

    Wang, Wei

    2014-01-01

    such as batteries and fuel cells. Increasing the energysuch as batteries and fuel cells 1 . In often cases SCs are

  13. 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

  14. Synthesis and characterization of nanostructured transition metal oxides for energy storage devices

    E-Print Network [OSTI]

    Kim, Jong Woung

    2012-01-01

    for energy storage systems such as power grids. Another partthe power grid. Although capacitive energy storage has not

  15. Improved layered mixed transition metal oxides for Li-ion batteries

    E-Print Network [OSTI]

    Doeff, Marca M.

    2010-01-01

    State Chemistry and Electrochemistry of LiCoi Ni, Mni/ 0 forState Chemistry and Electrochemistry of LiCo Nii/ Mn 0 forM. , "Structure and electrochemistry of LiNii/ Coi/ . M Mn

  16. Three-particle approximation for transition-metal oxides J. Lgsgaard and A. Svane

    E-Print Network [OSTI]

    Svane, Axel Torstein

    of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C, Denmark Received 6 May 1996; revised good spectral predictions, and it is natural to ask what makes the above-mentioned cases different less adequate, based as it is on correla- tion effects in a uniform electron gas. A suitable scheme

  17. Synthesis and characterization of nanostructured transition metal oxides for energy storage devices

    E-Print Network [OSTI]

    Kim, Jong Woung

    2012-01-01

    dehydrated amorphous Nb 2 O 5 aerogel, b) pseudohexagonal (phases: a) as-synthesized Nb 2 O 5 aerogel, b) dehydrated Nb2 O 5 aerogel, c) pseudohexagonal (TT- Nb 2 O 5 ), d)

  18. Improved layered mixed transition metal oxides for Li-ion batteries

    E-Print Network [OSTI]

    Doeff, Marca M.

    2010-01-01

    Mn 02 for lithium-ion batteries," Chem. Lett. , [3]0 for advanced lithium-ion batteries," J. Power Sources,Mni/ 0 for Advanced Lithium-Ion Batteries," J. Electrochem.

  19. Transition Metal Oxide Nanoparticles Anchored Nanocarbon Hybrid Foam for High Performance Electrochemical Energy Storage Applications

    E-Print Network [OSTI]

    Wang, Wei

    2014-01-01

    supercapacitors. Energy & Environmental Science Wang, W. etultracapacitors. Energy & Environmental Science 3, Xia, H. ,

  20. Charge Carrier Dynamics in Transition Metal Oxides Studied by Femtosecond Transient Extreme Ultraviolet Absorption Spectroscopy

    E-Print Network [OSTI]

    Jiang, Chang-Ming

    2015-01-01

    Fabricated by Atomic Layer Deposition. Nanotechnology 2010,2 Nanotube Arrays via Atomic Layer Deposition for Improvedsputtering or atomic layer deposition technique to prepare