National Library of Energy BETA

Sample records for zinc oxide upper

  1. Doped zinc oxide microspheres

    DOE Patents [OSTI]

    Arnold, Jr., Wesley D.; Bond, Walter D.; Lauf, Robert J.

    1993-01-01

    A new composition and method of making same for a doped zinc oxide microsphere and articles made therefrom for use in an electrical surge arrestor which has increased solid content, uniform grain size and is in the form of a gel.

  2. Doped zinc oxide microspheres

    DOE Patents [OSTI]

    Arnold, W.D. Jr.; Bond, W.D.; Lauf, R.J.

    1993-12-14

    A new composition and method of making same for a doped zinc oxide microsphere and articles made therefrom for use in an electrical surge arrestor which has increased solid content, uniform grain size and is in the form of a gel. 4 figures.

  3. Zinc oxide varistors and/or resistors

    DOE Patents [OSTI]

    Arnold, W.D. Jr.; Bond, W.D.; Lauf, R.J.

    1993-07-27

    Varistors and/or resistors are described that include doped zinc oxide gel microspheres. The doped zinc oxide gel microspheres preferably have from about 60 to about 95% by weight zinc oxide and from about 5 to about 40% by weight dopants based on the weight of the zinc oxide. The dopants are a plurality of dopants selected from silver salts, boron oxide, silicon oxide and hydrons oxides of aluminum, bismuth, cobalt, chromium, manganese, nickel, and antimony.

  4. Zinc oxide varistors and/or resistors

    DOE Patents [OSTI]

    Arnold, Jr., Wesley D.; Bond, Walter D.; Lauf, Robert J.

    1993-01-01

    Varistors and/or resistors that includes doped zinc oxide gel microspheres. The doped zinc oxide gel microspheres preferably have from about 60 to about 95% by weight zinc oxide and from about 5 to about 40% by weight dopants based on the weight of the zinc oxide. The dopants are a plurality of dopants selected from silver salts, boron oxide, silicon oxide and hydrons oxides of aluminum, bismuth, cobalt, chromium, manganese, nickel, and antimony.

  5. Directed spatial organization of zinc oxide nanostructures

    DOE Patents [OSTI]

    Hsu, Julia; Liu, Jun

    2009-02-17

    A method for controllably forming zinc oxide nanostructures on a surface via an organic template, which is formed using a stamp prepared from pre-defined relief structures, inking the stamp with a solution comprising self-assembled monolayer (SAM) molecules, contacting the stamp to the surface, such as Ag sputtered on Si, and immersing the surface with the patterned SAM molecules with a zinc-containing solution with pH control to form zinc oxide nanostructures on the bare Ag surface.

  6. Nanoscale Chemical Imaging of Zinc Oxide Nanowire Corrosion ...

    Office of Scientific and Technical Information (OSTI)

    Nanoscale Chemical Imaging of Zinc Oxide Nanowire Corrosion Citation Details In-Document Search Title: Nanoscale Chemical Imaging of Zinc Oxide Nanowire Corrosion Nanoscale ...

  7. Aluminum-doped Zinc Oxide Nanoink

    Energy Innovation Portal (Marketing Summaries) [EERE]

    2014-08-15

    Scientists at Berkeley Lab have developed a method for fabricating conductive aluminum-doped zinc oxide (AZO) nanocrystals that provide a lower cost, less toxic, earth-abundant alternative to the widely used transparent conductive oxide (TCO) indium tin oxide while offering comparable optical and electronic properties. TCOs are used in devices such as flat screen displays, photovoltaic cells, photochromic windows, chemical sensors, and biosensors....

  8. Aluminum doped zinc oxide for organic photovoltaics

    SciTech Connect (OSTI)

    Murdoch, G. B.; Hinds, S.; Sargent, E. H.; Tsang, S. W.; Mordoukhovski, L.; Lu, Z. H.

    2009-05-25

    Aluminum doped zinc oxide (AZO) was grown via magnetron sputtering as a low-cost alternative to indium tin oxide (ITO) for organic photovoltaics (OPVs). Postdeposition ozone treatment resulted in devices with lower series resistance, increased open-circuit voltage, and power conversion efficiency double that of devices fabricated on untreated AZO. Furthermore, cells fabricated using ozone treated AZO and standard ITO displayed comparable performance.

  9. Process for preparing zinc oxide-based sorbents

    DOE Patents [OSTI]

    Gangwal, Santosh Kumar; Turk, Brian Scott; Gupta, Raghubir Prasad

    2011-06-07

    The disclosure relates to zinc oxide-based sorbents, and processes for preparing and using them. The sorbents are preferably used to remove one or more reduced sulfur species from gas streams. The sorbents comprise an active zinc component, optionally in combination with one or more promoter components and/or one or more substantially inert components. The active zinc component is a two phase material, consisting essentially of a zinc oxide (ZnO) phase and a zinc aluminate (ZnAl.sub.2O.sub.4) phase. Each of the two phases is characterized by a relatively small crystallite size of typically less than about 500 Angstroms. Preferably the sorbents are prepared by converting a precursor mixture, comprising a precipitated zinc oxide precursor and a precipitated aluminum oxide precursor, to the two-phase, active zinc oxide containing component.

  10. Zinc oxide thin film acoustic sensor

    SciTech Connect (OSTI)

    Mohammed, Ali Jasim; Salih, Wafaa Mahdi; Hassan, Marwa Abdul Muhsien; Nusseif, Asmaa Deiaa; Kadhum, Haider Abdullah; Mansour, Hazim Louis

    2013-12-16

    This paper reports the implementation of (750 nm) thickness of Zinc Oxide (ZnO) thin film for the piezoelectric pressure sensors. The film was prepared and deposited employing the spray pyrolysis technique. XRD results show that the growth preferred orientation is the (002) plane. A polycrystalline thin film (close to mono crystallite like) was obtained. Depending on the Scanning Electron Microscopy photogram, the film homogeneity and thickness were shown. The resonance frequency measured (about 19 kHz) and the damping coefficient was calculated and its value was found to be about (2.5538), the thin film be haves as homogeneous for under and over damped. The thin film pressure sensing was approximately exponentially related with frequency, the thin film was observed to has a good response for mechanical stresses also it is a good material for the piezoelectric properties.

  11. Durable Zinc Oxide-Based Regenerable Sorbents for Desulfurization...

    Office of Scientific and Technical Information (OSTI)

    in a Fixed-Bed Reactor Citation Details In-Document Search Title: Durable Zinc Oxide-Based Regenerable Sorbents for Desulfurization of Syngas in a Fixed-Bed Reactor You are ...

  12. Acetone sensor based on zinc oxide hexagonal tubes

    SciTech Connect (OSTI)

    Hastir, Anita Singh, Onkar Anand, Kanika Singh, Ravi Chand

    2014-04-24

    In this work hexagonal tubes of zinc oxide have been synthesized by co-precipitation method. For structural, morphological, elemental and optical analysis synthesized powders were characterized by using x-ray diffraction, field emission scanning microscope, EDX, UV-visible and FTIR techniques. For acetone sensing thick films of zinc oxide have been deposited on alumina substrate. The fabricated sensors exhibited maximum sensing response towards acetone vapour at an optimum operating temperature of 400°C.

  13. Aluminum-doped Zinc Oxide Nanoink - Energy Innovation Portal

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

    Solar Photovoltaic Solar Photovoltaic Industrial Technologies Industrial Technologies Building Energy Efficiency Building Energy Efficiency Find More Like This Return to Search Aluminum-doped Zinc Oxide Nanoink Lawrence Berkeley National Laboratory Contact LBL About This Technology Technology Marketing Summary Scientists at Berkeley Lab have developed a method for fabricating conductive aluminum-doped zinc oxide (AZO) nanocrystals that provide a lower cost, less toxic, earth-abundant alternative

  14. Electrolyte optimization for cathodic growth of zinc oxide films

    SciTech Connect (OSTI)

    Izaki, Masanobu; Omi, Takashi

    1996-03-01

    Zinc oxide is of considerable interest to the optical and electronic industries, because of its electrical, optical, and acoustic characteristics. ZnO films can be prepared by several techniques, such as radio frequency (RF) magnetron sputtering, chemical vapor deposition, and molecular beam epitaxy. Preparation of oxide films by electrodeposition from aqueous solutions has several potential advantages over the other techniques. However, the formation of oxide films through electrochemical reactions have been demonstrated only on thallic oxide by Switzer and zirconium oxide by Gal-Or. In this work, the authors have prepared transparent ZnO films with optical bandgap energy of 3.3 eV by electrodeposition from an aqueous, 0.1 mol/liter zinc nitrate electrolyte. The deposition technology is still being developed. This paper reports the effects of the electrolyte concentration on the electrodeposition and properties of the ZnO films.

  15. Process for fabricating doped zinc oxide microsphere gel

    DOE Patents [OSTI]

    Arnold, Jr., Wesley D.; Bond, Walter D.; Lauf, Robert J.

    1991-01-01

    A new composition and method of making same for a doped zinc oxide microsphere and articles made therefrom for use in an electrical surge arrestor which has increased solid content, uniform grain size and is in the form of a gel.

  16. Process for fabricating doped zinc oxide microsphere gel

    DOE Patents [OSTI]

    Arnold, W.D. Jr.; Bond, W.D.; Lauf, R.J.

    1991-11-05

    Disclosed are a new composition and method of making same for a doped zinc oxide microsphere and articles made therefrom for use in an electrical surge arrestor which has increased solid content, uniform grain size and is in the form of a gel. 4 figures.

  17. Chemical vapor deposition of fluorine-doped zinc oxide

    DOE Patents [OSTI]

    Gordon, Roy G.; Kramer, Keith; Liang, Haifan

    2000-06-06

    Fims of fluorine-doped zinc oxide are deposited from vaporized precursor compounds comprising a chelate of a dialkylzinc, such as an amine chelate, an oxygen source, and a fluorine source. The coatings are highly electrically conductive, transparent to visible light, reflective to infrared radiation, absorbing to ultraviolet light, and free of carbon impurity.

  18. Interfacial electron transfer dynamics of photosensitized zinc oxide nanoclusters

    SciTech Connect (OSTI)

    Murakoshi, Kei; Yanagida, Shozo; Capel, M.

    1997-06-01

    The authors have prepared and characterized photosensitized zinc oxide (ZnO) nanoclusters, dispersed in methanol, using carboxylated coumarin dyes for surface adsorption. Femtosecond time-resolved emission spectroscopy allows the authors to measure the photo-induced charge carrier injection rate constant from the adsorbed photosensitizer to the n-type semiconductor nanocluster. These results are compared with other photosensitized semiconductors.

  19. Solvothermal routes for synthesis of zinc oxide nanorods.

    SciTech Connect (OSTI)

    Bell, Nelson Simmons

    2005-03-01

    Control of the synthesis of nanomaterials to produce morphologies exhibiting quantized properties will enable device integration of several novel applications including biosensors, catalysis, and optical devices. In this work, solvothermal routes to produce zinc oxide nanorods are explored. Much previous work has relied on the addition of growth directing/inhibiting agents to control morphology. It was found in coarsening studies that zinc oxide nanodots will ripen to nanorod morphologies at temperatures of 90 to 120 C. The resulting nanorods have widths of 9-12 nm average dimension, which is smaller than current methods for nanorod synthesis. Use of nanodots as nuclei may be an approach that will allow for controlled growth of higher aspect ratio nanorods.

  20. Zinc oxide-based sorbents and processes for preparing and using same

    DOE Patents [OSTI]

    Gangwal, Santosh Kumar; Turk, Brian Scott; Gupta, Raghubir Prasad

    2005-10-04

    Zinc oxide-based sorbents, and processes for preparing and using them are provided, wherein the sorbents are preferably used to remove one or more reduced sulfur species from gas streams. The sorbents contain an active zinc component, optionally in combination with one or more promoter components and/or one or more substantially inert components. The active zinc component is a two phase material, consisting essentially of a zinc oxide (ZnO) phase and a zinc aluminate (ZnAl.sub.2 O.sub.4) phase. Each of the two phases is characterized by a relatively small crystallite size of typically less than about 500 Angstroms. Preferably the sorbents are prepared by converting a precursor mixture, containing a precipitated zinc oxide precursor and a precipitated aluminum oxide precursor, to the two-phase, active zinc oxide containing component.

  1. Zinc-oxide-based sorbents and processes for preparing and using same

    DOE Patents [OSTI]

    Gangwal, Santosh Kumar; Turk, Brian Scott; Gupta, Raghubir Prasael

    2010-03-23

    Zinc oxide-based sorbents, and processes for preparing and using them are provided. The sorbents are preferably used to remove one or more reduced sulfur species from gas streams. The sorbents comprise an active zinc component, optionally in combination with one or more promoter components and/or one or more substantially inert components. The active zinc component is a two phase material, consisting essentially of a zinc oxide (ZnO) phase and a zinc aluminate (ZnAl.sub.2O.sub.4) phase. Each of the two phases is characterized by a relatively small crystallite size of typically less than about 500 Angstroms. Preferably the sorbents are prepared by converting a precursor mixture, comprising a precipitated zinc oxide precursor and a precipitated aluminum oxide precursor, to the two-phase, active zinc oxide containing component.

  2. Durable zinc oxide-containing sorbents for coal gas desulfurization

    DOE Patents [OSTI]

    Siriwardane, Ranjani V.

    1996-01-01

    Durable zinc-oxide containing sorbent pellets for removing hydrogen sulfide from a gas stream at an elevated temperature are made up to contain titania as a diluent, high-surface-area silica gel, and a binder. These materials are mixed, moistened, and formed into pellets, which are then dried and calcined. The resulting pellets undergo repeated cycles of sulfidation and regeneration without loss of reactivity and without mechanical degradation. Regeneration of the pellets is carried out by contacting the bed with an oxidizing gas mixture.

  3. Rare earth doped zinc oxide varistors

    DOE Patents [OSTI]

    McMillan, A.D.; Modine, F.A.; Lauf, R.J.; Alim, M.A.; Mahan, G.D.; Bartkowiak, M.

    1998-12-29

    A varistor includes a Bi-free, essentially homogeneous sintered body of a ceramic composition including, expressed as nominal weight %, 0.2--4.0% oxide of at least one rare earth element, 0.5--4.0% Co{sub 3}O{sub 4}, 0.05--0.4% K{sub 2}O, 0.05--0.2% Cr{sub 2}O{sub 3}, 0--0.2% CaO, 0.00005--0.01% Al{sub 2}O{sub 3}, 0--2% MnO, 0--0.05% MgO, 0--0.5% TiO{sub 3}, 0--0.2% SnO{sub 2}, 0--0.02% B{sub 2}O{sub 3}, balance ZnO. 4 figs.

  4. Rare earth doped zinc oxide varistors

    DOE Patents [OSTI]

    McMillan, April D.; Modine, Frank A.; Lauf, Robert J.; Alim, Mohammad A.; Mahan, Gerald D.; Bartkowiak, Miroslaw

    1998-01-01

    A varistor includes a Bi-free, essentially homogeneous sintered body of a ceramic composition including, expressed as nominal weight %, 0.2-4.0% oxide of at least one rare earth element, 0.5-4.0% Co.sub.3 O.sub.4, 0.05-0.4% K.sub.2 O, 0.05-0.2% Cr.sub.2 O.sub.3, 0-0.2% CaO, 0.00005-0.01% Al.sub.2 O.sub.3, 0-2% MnO, 0-0.05% MgO, 0-0.5% TiO.sub.3, 0-0.2% SnO.sub.2, 0-0.02% B.sub.2 O.sub.3, balance ZnO.

  5. Characterization of transparent zinc oxide films prepared by electrochemical reaction

    SciTech Connect (OSTI)

    Izaki, Masanobu; Omi, Takashi

    1997-06-01

    Transparent zinc oxide (ZnO) films have been grown by galvanostatic cathodic deposition onto conductive glasses from a simple aqueous zinc nitrate electrolyte maintained at 335 K. The as-deposited ZnO films were characterized with Fourier transform infrared absorption spectroscopy, x-ray diffraction, scanning electron microscopy, optical transmission and absorption studies, and measurement of sheet resistivity as a function of cathodic current density. The ZnO films prepared had a wurtzite structure and exhibited an optical bandgap energy of 3.3 eV which is characteristic of ZnO. At a low cathodic current density of 0.05 mA/cm{sup 2}, ZnO films with excellent electrical characteristics have been obtained. A 2 {micro}m thick ZnO film with an optical transmittance of 72% was deposited by electrolysis for approximately 20 min at a cathodic current density of 10 mA/cm{sup 2}.

  6. Structural characterization of impurified zinc oxide thin films

    SciTech Connect (OSTI)

    Trinca, L. M.; Galca, A. C. Stancu, V. Chirila, C. Pintilie, L.

    2014-11-05

    Europium doped zinc oxide (Eu:ZnO) thin films have been obtained by pulsed laser deposition (PLD). 002 textured thin films were achieved on glass and silicon substrates, while hetero-epilayers and homo-epilayers have been attained on single crystal SrTiO{sub 3} and ZnO, respectively. X-ray Diffraction (XRD) was employed to characterize the Eu:ZnO thin films. Extended XRD studies confirmed the different thin film structural properties as function of chosen substrates.

  7. Controlled Co(II) Doping of Zinc Oxide Nanocrystals

    SciTech Connect (OSTI)

    S Bohle; C Spina

    2011-12-31

    Dopants are non-native atoms commonly used to modify the properties of bulk semiconductors. In this paper we demonstrate that by controlling the addition of cobalt(II) to growing zinc oxide nanocrystals (ZnO NCs) it is possible to modulate the resulting properties. We show that the environment of cobalt may be controlled by varying the synthetic conditions, mainly through varying the time of dopant-precursor addition and concentration. These conditions prove critical to the resulting Co(II) configuration, which affects both the luminescent and photocatalytic properties of the ZnO NCs. Presynthetic doping with 2% Co(II) results in a 98% quenching of the visible emission of ZnO, whereas the same quantity doped post synthesis results in only a 60% quenching. The environment of cobalt in the ZnO wurtzite lattice is identified through UV-vis spectroscopy. The wurtzite structure of the ZnO lattice for all nanocrystalline species is confirmed through X-ray diffraction patterns obtained from a synchrotron radiation source. Postsynthetically doped Co(II) in ZnO NC is demonstrated to have potential applications as an 'on-off' sensor, as exemplified with nitric oxide.

  8. Ordered Nucleation Sites for the Growth of Zinc Oxide Nanofibers

    SciTech Connect (OSTI)

    Wang, J.; Ginley, D.S.; Shaheen, S.

    2006-01-01

    Organic photovoltaics (OPVs) offer a promising route to low cost photovoltaic (PV) technology that can be inexpensively manufactured on a large scale for use in power generation and commercial products. Solar power conversion efficiencies of laboratory scale OPV devices have recently reached ~5%; however, projected efficiencies of at least 10% will be required for commercialization. An analogous approach that has arisen recently that can potentially increase efficiencies employs metal oxide semiconductors as the electron acceptor, creating a hybrid organic-inorganic device. This approach offers the advantage that the conduction band of the oxide can be tuned in a systematic way through doping, thus potentially achieving higher photovoltages in the device. Additionally, nanostructures of these materials can be easily grown from precursor solutions, providing a technique to precisely control the nanoscale geometry. This work focuses on using ZnO, which is known to have high electron mobility (>100 cm2/Vs), as the electron acceptor. Nanofibers of ZnO can be grown from precursors such as zinc acetate or zinc nitrate to form arrays of nanofibers into which a conjugated polymer can be intercalated to form a composite PV device. The morphology of the nanofiber array is critical to the performance of the device, but current methods of nanofiber growth from a flat, polycrystalline nucleation layer allow for little morphological control. To overcome this limitation, we have created ordered arrays of ZnO nucleation sites with controllable size and spacing. Toluene solutions of diblock copolymer micelles with ZnCl2 incorporated into the micellar cores were spin-coated onto glass substrates and etched with an O2 plasma to yield hexagonally ordered arrays of ZnO nanoparticles that functioned as nucleation sites. Changing the concentration of ZnCl2 and the molecular weight and ratio of the diblock copolymer resulted in systematic variation in the size and spacing of the

  9. Zinc-oxide charge trapping memory cell with ultra-thin chromium-oxide trapping layer

    SciTech Connect (OSTI)

    El-Atab, Nazek; Rizk, Ayman; Nayfeh, Ammar; Okyay, Ali K.; UNAM-National Nanotechnology Research Center and Institute of Materials Science and Nanotechnology, Bilkent University, 06800 Ankara

    2013-11-15

    A functional zinc-oxide based SONOS memory cell with ultra-thin chromium oxide trapping layer was fabricated. A 5 nm CrO{sub 2} layer is deposited between Atomic Layer Deposition (ALD) steps. A threshold voltage (V{sub t}) shift of 2.6V was achieved with a 10V programming voltage. Also for a 2V V{sub t} shift, the memory with CrO{sub 2} layer has a low programming voltage of 7.2V. Moreover, the deep trapping levels in CrO{sub 2} layer allows for additional scaling of the tunnel oxide due to an increase in the retention time. In addition, the structure was simulated using Physics Based TCAD. The results of the simulation fit very well with the experimental results providing an understanding of the charge trapping and tunneling physics.

  10. Impacts of humidity and temperature on the performance of transparent conducting zinc oxide.

    SciTech Connect (OSTI)

    Granata, Jennifer E.; Yaklin, Melissa A.; Schneider, Duane Allen; Staiger, Chad Lynn; Norman, Kirsten

    2010-06-01

    The impact of humidity and temperature on a zinc oxide based transparent conducting oxide (TCO) was assessed under accelerated aging conditions. An in situ electroanalytical method was used to monitor the electrical properties for a conducting zinc oxide under controlled atmospheric (humidity, temperature and irradiation) conditions. A review of thin film photovoltaic (PV) literature has shown one major failure mode of cells/modules is associated with the ingress of water into modules in the field. Water contamination has been shown to degrade the performance of the TCO in addition to corroding interconnects and other conductive metals/materials associated with the module. Water ingress is particularly problematic in flexible thin film PV modules since traditional encapsulates such as poly(ethyl vinyl acetate) (EVA) have high water vapor transmission rates. The accelerated aging studies of the zinc oxide based TCOs will allow acceleration factors and kinetic parameters to be determined for reliability purposes.

  11. Different properties of aluminum doped zinc oxide nanostructured thin films prepared by radio frequency magnetron sputtering

    SciTech Connect (OSTI)

    Bidmeshkipour, Samina Shahtahmasebi, Nasser

    2013-06-15

    Aluminium doped zinc oxide (AZO) nanostructured thin films are prepared by radio frequency magnetron sputtering on glass substrate using specifically designed ZnO target containing different amount of Al{sub 2}O{sub 3} powder as the Al doping source. The optical properties of the aluminium doped zinc oxide films are investigated. The topography of the deposited films were investigated by Atomic Force Microscopy. Variation of the refractive index by annealing temperature are considered and it is seen that the refractive index increases by increasing the annealing temperature.

  12. Atomic layer deposition of tin oxide and zinc tin oxide using tetraethyltin and ozone

    SciTech Connect (OSTI)

    Warner, Ellis J.; Gladfelter, Wayne L.; Johnson, Forrest; Campbell, Stephen A.

    2015-03-15

    Silicon or glass substrates exposed to sequential pulses of tetraethyltin (TET) and ozone (O{sub 3}) were coated with thin films of SnO{sub 2}. Self-limiting deposition was found using 8 s pulse times, and a uniform thickness per cycle (TPC) of 0.2 nm/cycle was observed in a small, yet reproducible, temperature window from 290 to 320 °C. The as-deposited, stoichiometric SnO{sub 2} films were amorphous and transparent above 400 nm. Interspersing pulses of diethylzinc and O{sub 3} among the TET:O{sub 3} pulses resulted in deposition of zinc tin oxide films, where the fraction of tin, defined as [at. % Sn/(at. % Sn + at. % Zn)], was controlled by the ratio of TET pulses, specifically n{sub TET}:(n{sub TET} + n{sub DEZ}) where n{sub TET} and n{sub DEZ} are the number of precursor/O{sub 3} subcycles within each atomic layer deposition (ALD) supercycle. Based on film thickness and composition measurements, the TET pulse time required to reach saturation in the TPC of SnO{sub 2} on ZnO surfaces was increased to >30 s. Under these conditions, film stoichiometry as a function of the TET pulse ratio was consistent with the model devised by Elliott and Nilsen. The as-deposited zinc tin oxide (ZTO) films were amorphous and remained so even after annealing at 450 °C in air for 1 h. The optical bandgap of the transparent ZTO films increased as the tin concentration increased. Hall measurements established that the n-type ZTO carrier concentration was 3 × 10{sup 17} and 4 × 10{sup 18} cm{sup −3} for fractional tin concentrations of 0.28 and 0.63, respectively. The carrier mobility decreased as the concentration of tin increased. A broken gap pn junction was fabricated using ALD-deposited ZTO and a sputtered layer of cuprous oxide. The junction demonstrated ohmic behavior and low resistance consistent with similar junctions prepared using sputter-deposited ZTO.

  13. Multi-wavelength Raman scattering of nanostructured Al-doped zinc oxide

    SciTech Connect (OSTI)

    Russo, V.; Ghidelli, M.; Gondoni, P.

    2014-02-21

    In this work we present a detailed Raman scattering investigation of zinc oxide and aluminum-doped zinc oxide (AZO) films characterized by a variety of nanoscale structures and morphologies and synthesized by pulsed laser deposition under different oxygen pressure conditions. The comparison of Raman spectra for pure ZnO and AZO films with similar morphology at the nano/mesoscale allows to investigate the relation between Raman features (peak or band positions, width, relative intensity) and material properties such as local structural order, stoichiometry, and doping. Moreover Raman measurements with three different excitation lines (532, 457, and 325 nm) point out a strong correlation between vibrational and electronic properties. This observation confirms the relevance of a multi-wavelength Raman investigation to obtain a complete structural characterization of advanced doped oxide materials.

  14. Efficient inverted polymer solar cells based on conjugated polyelectrolyte and zinc oxide modified ITO electrode

    SciTech Connect (OSTI)

    Yuan, Tao; Zhu, Xiaoguang; Tu, Guoli; Zhou, Lingyu; Zhang, Jian

    2015-02-23

    Efficient inverted polymer solar cells (PSCs) were constructed by utilizing a conjugated polyelectrolyte PF{sub EO}SO{sub 3}Na and zinc oxide to modify the indium tin oxide (ITO) electrode. The ITO electrode modified by PF{sub EO}SO{sub 3}Na and zinc oxide possesses high transparency, increased electron mobility, smoothened surface, and lower work function. PTB7:PC{sub 71}BM inverted PSCs containing the modified ITO electrode achieved a high power conversion efficiency (PCE) of 8.49%, exceeding that of the control device containing a ZnO modified ITO electrode (7.48%). Especially, PCE-10:PC{sub 71}BM inverted polymer solar cells achieved a high PCE up to 9.4%. These results demonstrate a useful approach to improve the performance of inverted polymer solar cells.

  15. Local environment in poly(ethylene oxide)-zinc bromide complexes

    SciTech Connect (OSTI)

    Chintipalli, S.; Frech, R.; Grady, B.

    1996-12-31

    This study examines atomic-level local environments in Poly(ethylene oxide)-zinc bromide+lithium bromide (PEO){sub 20}[(ZnBr{sub 2}){sub 1-x} (LiBr){sub x}] complexes using Raman spectroscopy and x-ray absorption spectroscopy (XAS). Specific features in the Raman spectra were used to show that the zinc bromide species changes from ZnBr{sub 2} to ZnBr{sub 3}{sup -} to ZnBr{sub 4}{sup 2-} when x is varied from 0 to 0.8. XAS showed a similar change in oxygen coordination number from 4 to 0 when x is varied from 0 to 0.8. This study shows that lithium atoms displace zinc atoms from ether oxygen speciation indicating that lithium coordination to ether oxygens is thermodynamically favored. The effect of adding polar plasticizers is also discussed.

  16. Pencil-like zinc oxide micro/nano-scale structures: Hydrothermal synthesis, optical and photocatalytic properties

    SciTech Connect (OSTI)

    Moulahi, A.; Sediri, F.

    2013-10-15

    Graphical abstract: - Highlights: Zinc oxide micro/nanopencils have been synthesized hydrothermally. Photocatalytic activity has been evaluated by the degradation of methylene blue under UV light irradiation. ZnO nanopencils exhibit much higher photocatalytic activity than the commercial ZnO. - Abstract: Zinc oxide micro/nanopencils have been successfully synthesized by hydrothermal process using zinc acetate and diamines as structure-directing agents. The morphology, the structure, the crystallinity and the composition of the materials were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). The optical properties of synthesized ZnO were investigated by UVvis spectroscopy. The photocatalytic activity of the material has been evaluated by the degradation of methylene blue under UV irradiation. As a result, after the lapse of 150 min, around 82% bleaching was observed, with ZnO nanopencils yielding more photodegradation compared to that of commercial ZnO (61%)

  17. Colloidal infrared reflective and transparent conductive aluminum-doped zinc oxide nanocrystals

    DOE Patents [OSTI]

    Buonsanti, Raffaella; Milliron, Delia J

    2015-02-24

    The present invention provides a method of preparing aluminum-doped zinc oxide (AZO) nanocrystals. In an exemplary embodiment, the method includes (1) injecting a precursor mixture of a zinc precursor, an aluminum precursor, an amine, and a fatty acid in a solution of a vicinal diol in a non-coordinating solvent, thereby resulting in a reaction mixture, (2) precipitating the nanocrystals from the reaction mixture, thereby resulting in a final precipitate, and (3) dissolving the final precipitate in an apolar solvent. The present invention also provides a dispersion. In an exemplary embodiment, the dispersion includes (1) nanocrystals that are well separated from each other, where the nanocrystals are coated with surfactants and (2) an apolar solvent where the nanocrystals are suspended in the apolar solvent. The present invention also provides a film. In an exemplary embodiment, the film includes (1) a substrate and (2) nanocrystals that are evenly distributed on the substrate.

  18. Structural and optical properties of zinc oxide film using RF-sputtering technique

    SciTech Connect (OSTI)

    Hashim, A. J.; Jaafar, M. S.; Ghazai, Alaa J.

    2012-11-27

    This paper reports the fabrication of zinc oxide (ZnO) film using RF-sputtering technique. Determination of the structural properties using High Resolution X-ray Diffraction (HRXRD) confirmed that ZnO film deposited on silicon (Si) substrate has a high quality. This result is in line with the Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) which were used to image the morphology of the film, in which a rough surface was demonstrated. Photoluminescence (PL) emission is included to study the optical properties of ZnO film that shows two PL peak in the UV region at 371 nm and in visible region at 530 nm respectively.

  19. Surface nanostructuring by ion-induced localized plasma expansion in zinc oxide

    SciTech Connect (OSTI)

    El-Said, A. S. E-mail: a.s.el-said@hzdr.de; Moslem, W. M.; Djebli, M.

    2014-06-09

    Creation of hillock-like nanostructures on the surface of zinc oxide single crystals by irradiation with slow highly charged ions is reported. At constant kinetic energy, the nanostructures were only observed after irradiation with ions of potential energies above a threshold between 19.1 keV and 23.3 keV. The size of the nanostructures increases as a function of potential energy. A plasma expansion approach is used to explain the nanostructures creation. The calculations showed that the surface nanostructures became taller with the increase of ionic temperature. The influence of charged cluster formation and the relevance of their polarity are discussed.

  20. Sensing behaviour of nanosized zinc-tin composite oxide towards liquefied petroleum gas and ethanol

    SciTech Connect (OSTI)

    Singh, Ravi Chand; Singh, Onkar; Singh, Manmeet Pal; Chandi, Paramdeep Singh; Thangaraj, R.

    2010-09-15

    A chemical route has been used to synthesize composite oxides of zinc and tin. An ammonia solution was added to equal amounts of zinc and tin chloride solutions of same molarities to obtain precipitates. Three portions of these precipitates were annealed at 400, 600 and 800 {sup o}C, respectively. Results of X-ray diffraction and transmission electron microscopy clearly depicted coexistence of phases of nano-sized SnO{sub 2}, ZnO, Zn{sub 2}SnO{sub 4} and ZnSnO{sub 3}. The effect of annealing on structure, morphology and sensing has been observed as well. It has been observed that annealing promoted growth of Zn{sub 2}SnO{sub 4} and ZnSnO{sub 3} at the expense of zinc. The sensing response of fabricated sensors from these materials to 250 ppm LPG and ethanol has been investigated. The sensor fabricated from powder annealed at 400 {sup o}C responded better to LPG than ethanol.

  1. Effect of nitrogen doping on wetting and photoactive properties of laser processed zinc oxide-graphene oxide nanocomposite layers

    SciTech Connect (OSTI)

    György, E.; Pérez del Pino, A.; Logofatu, C.; Duta, A.; Isac, L.

    2014-07-14

    Zinc oxide-graphene oxide nanocomposite layers were submitted to laser irradiation in air or controlled nitrogen atmosphere using a frequency quadrupled Nd:YAG (λ = 266 nm, τ{sub FWHM} ≅ 3 ns, ν = 10 Hz) laser source. The experiments were performed in air at atmospheric pressure or in nitrogen at a pressure of 2 × 10{sup 4} Pa. The effect of the irradiation conditions, incident laser fluence value, and number of subsequent laser pulses on the surface morphology of the composite material was systematically investigated. The obtained results reveal that nitrogen incorporation improves significantly the wetting and photoactive properties of the laser processed layers. The kinetics of water contact angle variation when the samples are submitted to laser irradiation in nitrogen are faster than that of the samples irradiated in air, the surfaces becoming super-hydrophilic under UV light irradiation.

  2. Plasmon resonance and perfect light absorption in subwavelength trench arrays etched in gallium-doped zinc oxide film

    SciTech Connect (OSTI)

    Hendrickson, Joshua R. Leedy, Kevin; Cleary, Justin W.; Vangala, Shivashankar; Nader, Nima; Guo, Junpeng

    2015-11-09

    Near-perfect light absorption in subwavelength trench arrays etched in highly conductive gallium-doped zinc oxide films was experimentally observed in the mid infrared regime. At wavelengths corresponding to the resonant excitation of surface plasmons, up to 99% of impinging light is efficiently trapped and absorbed in the periodic trenches. Scattering cross sectional calculations reveal that each individual trench acts like a vertical split ring resonator with a broad plasmon resonance spectrum. The coupling of these individual plasmon resonators in the grating structure leads to enhanced photon absorption and significant resonant spectral linewidth narrowing. Ellipsometry measurements taken before and after device fabrication result in different permittivity values for the doped zinc oxide material, indicating that localized annealing occurred during the plasma etching process due to surface heating. Simulations, which incorporate a 50 nm annealed region at the zinc oxide surface, are in a good agreement with the experimental results.

  3. Estimated safe zinc and copper levels for chinook salmon, Oncorhynchus tshawytscha, in the upper Sacremento River, California

    SciTech Connect (OSTI)

    Finlayson, B.J.; Verrue, K.M.

    1980-04-01

    Experiments to determine the tolerance levels of chinook salmon, Oncorhynchus tshawytscha, to copper and zinc from acid wastes in a tributary to the Sacremento River are described. Copper-zinc ratios in the acid mine waste in Spring Creek varied between 1:2 and 1:12, with pH ranging from 6.6 to 7.4.

  4. Characterization of Monolayer Formation on Aluminum-Doped Zinc Oxide Thin Films

    SciTech Connect (OSTI)

    Rhodes,C.; Lappi, S.; Fischer, D.; Sambasivan, S.; Genzer, J.; Franzen, S.

    2008-01-01

    The optical and electronic properties of aluminum-doped zinc oxide (AZO) thin films on a glass substrate are investigated experimentally and theoretically. Optical studies with coupling in the Kretschmann configuration reveal an angle-dependent plasma frequency in the mid-IR for p-polarized radiation, suggestive of the detection of a Drude plasma frequency. These studies are complemented by oxygen depletion density functional theory studies for the calculation of the charge carrier concentration and plasma frequency for bulk AZO. In addition, we report on the optical and physical properties of thin film adlayers of n-hexadecanethiol (HDT) and n-octadecanethiol (ODT) self-assembled monolayers (SAMs) on AZO surfaces using reflectance FTIR spectroscopy, X-ray photoelectron spectroscopy (XPS), contact angle, and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. Our characterization of the SAM deposition onto the AZO thin film reveals a range of possible applications for this conducting metal oxide.

  5. Origin of deep subgap states in amorphous indium gallium zinc oxide: Chemically disordered coordination of oxygen

    SciTech Connect (OSTI)

    Sallis, S.; Williams, D. S.; Butler, K. T.; Walsh, A.; Quackenbush, N. F.; Junda, M.; Podraza, N. J.; Fischer, D. A.; Woicik, J. C.; White, B. E.; Piper, L. F. J.

    2014-06-09

    The origin of the deep subgap states in amorphous indium gallium zinc oxide (a-IGZO), whether intrinsic to the amorphous structure or not, has serious implications for the development of p-type transparent amorphous oxide semiconductors. We report that the deep subgap feature in a-IGZO originates from local variations in the oxygen coordination and not from oxygen vacancies. This is shown by the positive correlation between oxygen composition and subgap intensity as observed with X-ray photoelectron spectroscopy. We also demonstrate that the subgap feature is not intrinsic to the amorphous phase because the deep subgap feature can be removed by low-temperature annealing in a reducing environment. Atomistic calculations of a-IGZO reveal that the subgap state originates from certain oxygen environments associated with the disorder. Specifically, the subgap states originate from oxygen environments with a lower coordination number and/or a larger metal-oxygen separation.

  6. Flexible indium zinc oxide/Ag/indium zinc oxide multilayer electrode grown on polyethersulfone substrate by cost-efficient roll-to-roll sputtering for flexible organic photovoltaics

    SciTech Connect (OSTI)

    Park, Yong-Seok; Kim, Han-Ki

    2010-01-15

    The authors describe the preparation and characteristics of flexible indium zinc oxide (IZO)-Ag-IZO multilayer electrodes grown on flexible polyethersulfone (PES) substrates using a roll-to-roll sputtering system for use in flexible organic photovoltaics. By the continuous roll-to-roll sputtering of the bottom IZO, Ag, and top IZO layers at room temperature, they were able to fabricate a high quality IZO-Ag-IZO multilayer electrode with a sheet resistance of 6.15 {epsilon}/square, optical transmittance of 87.4%, and figure of merit value of 42.03x10{sup -3} {Omega}{sup -1} on the PES substrate. In addition, the IZO-Ag-IZO multilayer electrode exhibited superior flexibility to the roll-to-roll sputter grown single ITO electrode due to the existence of a ductile Ag layer between the IZO layers and stable amorphous structure of the IZO film. Furthermore, the flexible organic solar cells (OSCs) fabricated on the roll-to-roll sputter grown IZO-Ag-IZO electrode showed higher power efficiency (3.51%) than the OSCs fabricated on the roll-to-roll sputter grown single ITO electrode (2.67%).

  7. Synthesis of supported silver nano-spheres on zinc oxide nanorods for visible light photocatalytic applications

    SciTech Connect (OSTI)

    Saoud, Khaled; Alsoubaihi, Rola; Bensalah, Nasr; Bora, Tanujjal; Bertino, Massimo; Dutta, Joydeep

    2015-03-15

    Highlights: Synthesis of supported Ag NPs on ZnO nanorods using open vessel microwave reactor. Use of the Ag/ZnO NPs as an efficient visible light photocatalyst. Complete degradation of methylene blue in 1 h with 0.5 g/L Ag/ZnO NPs. - Abstract: We report the synthesis of silver (Ag) nano-spheres (NS) supported on zinc oxide (ZnO) nanorods through two step mechanism, using open vessel microwave reactor. Direct reduction of ZnO from zinc nitrates was followed by deposition precipitation of the silver on the ZnO nanorods. The supported Ag/ZnO nanoparticles were then characterized by electron microscopy, X-ray diffraction, FTIR, photoluminescence and UVvis spectroscopy. The visible light photocatalytic activity of Ag/ZnO system was investigated using a test contaminant, methylene blue (MB). Almost complete removal of MB in about 60 min for doses higher than 0.5 g/L of the Ag/ZnO photocatalyst was achieved. This significant improvement in the photocatalytic efficiency of Ag/ZnO photocatalyst under visible light irradiation can be attributed to the presence of Ag nanoparticles on the ZnO nanoparticles which greatly enhances absorption in the visible range of solar spectrum enabled by surface plasmon resonance effect from Ag nanoparticles.

  8. Hydrothermal synthesis of nanostructured zinc oxide and study of their optical properties

    SciTech Connect (OSTI)

    Moulahi, A.; Sediri, F.; Gharbi, N.

    2012-03-15

    Highlights: Black-Right-Pointing-Pointer Nanostructured ZnO were successfully obtained by a hydrothermal route. Black-Right-Pointing-Pointer Inorganic precursor and molar ratio are key factors for morphology and particle size. Black-Right-Pointing-Pointer Optical properties were also studied. -- Abstract: Nanostructured ZnO (nanorods, nanoshuttles) have been synthesized by hydrothermal approach using ZnCl{sub 2} or Zn(NO{sub 3}){sub 2}{center_dot}6H{sub 2}O as zinc sources and cetyltrimethylammonium bromide as structure-directing agent. Techniques X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-visible absorption, Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy have been used to characterize the structure, morphology and composition of the nanostructured zinc oxide. The optical properties of the as-obtained materials were also studied and showing that it is possible to apply the ZnO nanoshuttles and nanorods on the UV filter, photocatalysis, and special optical devices.

  9. Efficient indium-tin-oxide free inverted organic solar cells based on aluminum-doped zinc oxide cathode and low-temperature aqueous solution processed zinc oxide electron extraction layer

    SciTech Connect (OSTI)

    Chen, Dazheng; Zhang, Chunfu Wang, Zhizhe; Zhang, Jincheng; Tang, Shi; Wei, Wei; Sun, Li; Hao, Yue

    2014-06-16

    Indium-tin-oxide (ITO) free inverted organic solar cells (IOSCs) based on aluminum-doped zinc oxide (AZO) cathode, low-temperature aqueous solution processed zinc oxide (ZnO) electron extraction layer, and poly(3-hexylthiophene-2, 5-diyl):[6, 6]-phenyl C{sub 61} butyric acid methyl ester blend were realized in this work. The resulted IOSC with ZnO annealed at 150 °C shows the superior power conversion efficiency (PCE) of 3.01%, if decreasing the ZnO annealing temperature to 100 °C, the obtained IOSC also shows a PCE of 2.76%, and no light soaking issue is observed. It is found that this ZnO film not only acts as an effective buffer layer but also slightly improves the optical transmittance of AZO substrates. Further, despite the relatively inferior air-stability, these un-encapsulated AZO/ZnO IOSCs show comparable PCEs to the referenced ITO/ZnO IOSCs, which demonstrates that the AZO cathode is a potential alternative to ITO in IOSCs. Meanwhile, this simple ZnO process is compatible with large area deposition and plastic substrates, and is promising to be widely used in IOSCs and other relative fields.

  10. Zinc Oxide Thin Films Fabricated with Direct Current Magnetron Sputtering Deposition Technique

    SciTech Connect (OSTI)

    Hoon, Jian-Wei; Chan, Kah-Yoong; Krishnasamy, Jegenathan; Tou, Teck-Yong

    2011-03-30

    Zinc oxide (ZnO) is a very promising material for emerging large area electronic applications including thin-film sensors, transistors and solar cells. We fabricated ZnO thin films by employing direct current (DC) magnetron sputtering deposition technique. ZnO films with different thicknesses ranging from 100 nm to 1020 nm were deposited on silicon (Si) substrate. The deposition pressure was varied from 12 mTorr to 25 mTorr. The influences of the film thickness and the deposition pressure on structural properties of the ZnO films were investigated using Mahr surface profilometer and atomic force microscopy (AFM). The experimental results reveal that the film thickness and the deposition pressure play significant role in the structural formation of the deposited ZnO thin films. ZnO films deposited on Si substrates are promising for variety of thin-film sensor applications.

  11. High sensitive formaldehyde graphene gas sensor modified by atomic layer deposition zinc oxide films

    SciTech Connect (OSTI)

    Mu, Haichuan; Zhang, Zhiqiang; Wang, Keke; Xie, Haifen, E-mail: hfxie@ecust.edu.cn [Department of Physics, School of Science, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237 (China); Zhao, Xiaojing; Liu, Feng [Department of Physics, Shanghai Normal University, 100 Guilin Road, Shanghai 200234 (China)

    2014-07-21

    Zinc oxide (ZnO) thin films with various thicknesses were fabricated by Atomic Layer Deposition on Chemical Vapor Deposition grown graphene films and their response to formaldehyde has been investigated. It was found that 0.5?nm ZnO films modified graphene sensors showed high response to formaldehyde with the resistance change up to 52% at the concentration of 9 parts-per-million (ppm) at room temperature. Meanwhile, the detection limit could reach 180 parts-per-billion (ppb) and fast response of 36?s was also obtained. The high sensitivity could be attributed to the combining effect from the highly reactive, top mounted ZnO thin films, and high conductive graphene base network. The dependence of ZnO films surface morphology and its sensitivity on the ZnO films thickness was also investigated.

  12. Highly Attrition Resistant Zinc Oxide-Based Sorbents for H2S Removal by Spray Drying Technique

    SciTech Connect (OSTI)

    Ryu, C.K.; Lee, J.B.; Ahn, D.H.; Kim, J.J.; Yi, C.K.

    2002-09-19

    Primary issues for the fluidized-bed/transport reactor process are high attrition resistant sorbent, its high sorption capacity and regenerability, durability, and cost. The overall objective of this project is the development of a superior attrition resistant zinc oxide-based sorbent for hot gas cleanup in integrated coal gasification combined cycle (IGCC). Sorbents applicable to a fluidized-bed hot gas desulfurization process must have a high attrition resistance to withstand the fast solid circulation between a desulfurizer and a regenerator, fast kinetic reactions, and high sulfur sorption capacity. The oxidative regeneration of zinc-based sorbent usually initiated at greater than 600 C with highly exothermic nature causing deactivation of sorbent as well as complication of sulfidation process by side reaction. Focusing on solving the sorbent attrition and regenerability of zinc oxide-based sorbent, we have adapted multi-binder matrices and direct incorporation of regeneration promoter. The sorbent forming was done with a spray drying technique that is easily scalable to commercial quantity.

  13. Structural and optical properties of DC reactive magnetron sputtered zinc aluminum oxide thin films

    SciTech Connect (OSTI)

    Kumar, B. Rajesh; Rao, T. Subba

    2014-10-15

    Highly transparent conductive Zinc Aluminum Oxide (ZAO) thin films have been deposited on glass substrates using DC reactive magnetron sputtering method. The thin films were deposited at 200 C and post-deposition annealing from 15 to 90 min. XRD patterns of ZAO films exhibit only (0 0 2) diffraction peak, indicating that they have c-axis preferred orientation perpendicular to the substrate. Scanning electron microscopy (SEM) is used to study the surface morphology of the films. The grain size obtained from SEM images of ZAO thin films are found to be in the range of 20 - 26 nm. The minimum resistivity of 1.74 10{sup ?4} ? cm and an average transmittance of 92% are obtained for the thin film post annealed for 30 min. The optical band gap of ZAO thin films increased from 3.49 to 3.60 eV with the increase of annealing time due to Burstein-Moss effect. The optical constants refractive index (n) and extinction coefficient (k) were also determined from the optical transmission spectra.

  14. Electric radiation mapping of silver/zinc oxide nanoantennas by using electron holography

    SciTech Connect (OSTI)

    Sanchez, J. E.; Mendoza-Santoyo, F.; Cantu-Valle, J.; Velazquez-Salazar, J.; Jos Yacaman, M.; Ponce, A.; Gonzlez, F. J.; Diaz de Leon, R.

    2015-01-21

    In this work, we report the fabrication of self-assembled zinc oxide nanorods grown on pentagonal faces of silver nanowires by using microwaves irradiation. The nanostructures resemble a hierarchal nanoantenna and were used to study the far and near field electrical metal-semiconductor behavior from the electrical radiation pattern resulting from the phase map reconstruction obtained using off-axis electron holography. As a comparison, we use electric numerical approximations methods for a finite number of ZnO nanorods on the Ag nanowires and show that the electric radiation intensities maps match closely the experimental results obtained with electron holography. The time evolution of the radiation pattern as generated from the nanostructure was recorded under in-situ radio frequency signal stimulation, in which the generated electrical source amplitude and frequency were varied from 0 to 5 V and from 1 to 10?MHz, respectively. The phase maps obtained from electron holography show the change in the distribution of the electric radiation pattern for individual nanoantennas. The mapping of this electrical behavior is of the utmost importance to gain a complete understanding for the metal-semiconductor (Ag/ZnO) heterojunction that will help to show the mechanism through which these receiving/transmitting structures behave at nanoscale level.

  15. Synthesis of Uniformly Distributed Single- and Double-sided Zinc Oxide (ZnO) Nanocombs

    SciTech Connect (OSTI)

    Petford-Long, Amanda K.; Liu, Yuzi; Altintas Yildirim, Ozlem

    2015-11-15

    Uniformly distributed single- and double-sided zinc oxide (ZnO) nanocomb structures have been prepared by a vapor-liquid-solid technique from a mixture of ZnO nanoparticles and graphene nanoplatelets. The ZnO seed nanoparticles were synthesized via a simple precipitation method. The structure of the ZnO nanocombs could easily be controlled by tuning the carrier-gas flow rate during growth. Higher flow rate resulted in the formation of uniformly-distributed single-sided comb structures with nanonail-shaped teeth, as a result of the self-catalysis effect of the catalytically active Zn-terminated polar (0001) surface. Lower gas flow rate was favorable for production of double-sided comb structures with the two sets of teeth at an angle of similar to 110 degrees to each other along the comb ribbon, which was attributed to the formation of a bicrystal nanocomb ribbon. The formation of such a double-sided structure with nanonail-shaped teeth has not previously been reported.

  16. 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.

  17. Photoluminescence emission at room temperature in zinc oxide nano-columns

    SciTech Connect (OSTI)

    Rocha, L.S.R.; Deus, R.C.; Foschini, C.R.; Simes, A.Z.

    2014-02-01

    Highlights: ZnO nanoparticles were obtained by microwave-hydrothermal method. X-ray diffraction reveals a hexagonal structure. Photoluminescence emission evidenced two absorption peaks, at around 480 nm and 590 nm wavelengths. - Abstract: Hydrothermal microwave method (HTMW) was used to synthesize crystalline zinc oxide (ZnO) nano-columns at the temperature of 120 C with a soaking time of 8 min. ZnO nano-columns were characterized by using X-ray analyses (XRD), infrared spectroscopy (FT-IR), thermogravimetric analyses (TG-DTA), field emission gun and transmission electron microscopy (FEG-SEM and TEM) and photoluminescence properties (PL). XRD results indicated that the ZnO nano-columns are free of any impurity phase and crystallize in the hexagonal structure. Typical FT-IR spectra for ZnO nano-columns presented well defined bands, indicating a substantial short-range order in the system. PL spectra consist of a broad band at 590 nm and narrow band at 480 nm corresponding to a near-band edge emission related to the recombination of excitons and level emission related to structural defects. These results show that the HTMW synthesis route is rapid, cost effective, and could be used as an alternative to obtain ZnO nano-columns in the temperature of 120 C for 8 min.

  18. Production of zinc pellets

    DOE Patents [OSTI]

    Cooper, J.F.

    1996-11-26

    Uniform zinc pellets are formed for use in batteries having a stationary or moving slurry zinc particle electrode. The process involves the cathodic deposition of zinc in a finely divided morphology from battery reaction product onto a non-adhering electrode substrate. The mossy zinc is removed from the electrode substrate by the action of gravity, entrainment in a flowing electrolyte, or by mechanical action. The finely divided zinc particles are collected and pressed into pellets by a mechanical device such as an extruder, a roller and chopper, or a punch and die. The pure zinc pellets are returned to the zinc battery in a pumped slurry and have uniform size, density and reactivity. Applications include zinc-air fuel batteries, zinc-ferricyanide storage batteries, and zinc-nickel-oxide secondary batteries. 6 figs.

  19. Production of zinc pellets

    DOE Patents [OSTI]

    Cooper, John F.

    1996-01-01

    Uniform zinc pellets are formed for use in batteries having a stationary or moving slurry zinc particle electrode. The process involves the cathodic deposition of zinc in a finely divided morphology from battery reaction product onto a non-adhering electrode substrate. The mossy zinc is removed from the electrode substrate by the action of gravity, entrainment in a flowing electrolyte, or by mechanical action. The finely divided zinc particles are collected and pressed into pellets by a mechanical device such as an extruder, a roller and chopper, or a punch and die. The pure zinc pellets are returned to the zinc battery in a pumped slurry and have uniform size, density and reactivity. Applications include zinc-air fuel batteries, zinc-ferricyanide storage batteries, and zinc-nickel-oxide secondary batteries.

  20. The novel zinc cluster regulator Tog1 plays important roles in oleate utilization and oxidative stress response in Saccharomyces cerevisiae

    SciTech Connect (OSTI)

    Thepnok, Piyasuda; Ratanakhanokchai, Khanok; Soontorngun, Nitnipa

    2014-08-08

    Highlights: TOG1 deletion results in defective growth on non-fermentable carbon sources. Removal of TOG1 sensitizes cells to oxidative stress. Tog1 directly binds and activates expression of oleate utilizing genes. The ?tog1 cells display reduced peroxisomal content in oleate culture. S. cerevisiae zinc cluster Tog1 is a novel activator of oleate utilization. - Abstract: Many zinc cluster proteins have been shown to play a role in the transcriptional regulation of glucose-repressible genes during glucose exhaustion and diauxic shift. Here, we studied an additional member of this family called Yer184c (herein called Tog1) for transcriptional regulator of oleate. Our results showed that a ?tog1 strain displays impaired growth with several non-fermentable carbons. Tog1 is also implicated in oxidative stress tolerance. Importantly, during the glucoseoleate shift, combined results from quantitative real time-PCR and chromatin immunoprecipitation (ChIP) experiments showed that Tog1 acts as a direct activator of oleate utilizing genes, encoded key enzymes in ?-Oxidation and NADPH regeneration (POX1, FOX2, POT1 and IDP2), the glyoxylate shunt (MLS1 and ICL1), and gluconeogenesis (PCK1 and FBP1). A transmission electron microscopy (TEM) analysis of the ?tog1 strain assayed with oleate also revealed a substantial decrease in peroxisome abundance that is vital for fatty acid oxidation. Overall, our results clearly demonstrated that Tog1 is a newly characterized zinc cluster regulator that functions in the complex network of non-fermentable carbon metabolism in Saccharomycescerevisiae.

  1. Zinc oxide modified with benzylphosphonic acids as transparent electrodes in regular and inverted organic solar cell structures

    SciTech Connect (OSTI)

    Lange, Ilja; Reiter, Sina; Kniepert, Juliane; Piersimoni, Fortunato; Brenner, Thomas; Neher, Dieter; Pätzel, Michael; Hildebrandt, Jana; Hecht, Stefan

    2015-03-16

    An approach is presented to modify the work function of solution-processed sol-gel derived zinc oxide (ZnO) over an exceptionally wide range of more than 2.3 eV. This approach relies on the formation of dense and homogeneous self-assembled monolayers based on phosphonic acids with different dipole moments. This allows us to apply ZnO as charge selective bottom electrodes in either regular or inverted solar cell structures, using poly(3-hexylthiophene):phenyl-C71-butyric acid methyl ester as the active layer. These devices compete with or even surpass the performance of the reference on indium tin oxide/poly(3,4-ethylenedioxythiophene) polystyrene sulfonate. Our findings highlight the potential of properly modified ZnO as electron or hole extracting electrodes in hybrid optoelectronic devices.

  2. Synthesis of silica coated zinc oxidepoly(ethylene-co-acrylic acid) matrix and its UV shielding evaluation

    SciTech Connect (OSTI)

    Ramasamy, Mohankandhasamy; Kim, Yu Jun; Gao, Haiyan; Yi, Dong Kee; An, Jeong Ho

    2014-03-01

    Graphical abstract: - Highlights: Well layer thickness controlled silica shell was made on ZnO nanoparticles. PEAA, an interfacial agent is used to make nanocompositepolymer matrix by twin-screw extruder. Si-ZnO/PEAA matrix is highly stable and UV protective as compared to ZnO/PEAA matrix. Nanoparticle embedded polymer matrix is suggested to make UV shielding fabrics with Nylon4. - Abstract: Silica coated zinc oxide nanoparticles (Si-ZnO NPs) (7 nm thick) were synthesized successfully and melt blended with poly(ethylene-co-acrylic acid) (PEAA resin) to improving ultraviolet (UV) shielding of zinc oxide nanoparticles (ZnO NPs). The photostability of both the ZnO NPs and Si-ZnO NPs were analyzed by the difference in photoluminescence (PL) and by methylene blue (MB) degradation. Photo-degradation studies confirmed that Si-ZnO NPs are highly photostable compared to ZnO NPs. The melt blended matrices were characterized by field emission scanning electron microscopy interfaced with energy dispersive X-ray spectroscopy (FE-SEM-EDX). The UV shielding property was analyzed from the transmittance spectra of UVvisible (UVvis) spectroscopy. The results confirmed fine dispersion of thick Si-ZnO NPs in the entire resin matrix. Moreover, the Si-ZnO/PEAA showed about 97% UV shielding properties than the ZnO/PEAA.

  3. Zinc oxyfluoride transparent conductor

    DOE Patents [OSTI]

    Gordon, Roy G.

    1991-02-05

    Transparent, electrically conductive and infrared-reflective films of zinc oxyfluoride are produced by chemical vapor deposition from vapor mixtures of zinc, oxygen and fluorine-containing compounds. The substitution of fluorine for some of the oxygen in zinc oxide results in dramatic increases in the electrical conductivity. For example, diethyl zinc, ethyl alcohol and hexafluoropropene vapors are reacted over a glass surface at 400.degree. C. to form a visibly transparent, electrically conductive, infrared reflective and ultraviolet absorptive film of zinc oxyfluoride. Such films are useful in liquid crystal display devices, solar cells, electrochromic absorbers and reflectors, energy-conserving heat mirrors, and antistatic coatings.

  4. Recovery from ultraviolet-induced threshold voltage shift in indium gallium zinc oxide thin film transistors by positive gate bias

    SciTech Connect (OSTI)

    Liu, P.; Chen, T. P.; Li, X. D.; Wong, J. I.; Liu, Z.; Liu, Y.; Leong, K. C.

    2013-11-11

    The effect of short-duration ultraviolet (UV) exposure on the threshold voltage (V{sub th}) of amorphous indium gallium zinc oxide thin film transistors (TFTs) and its recovery characteristics were investigated. The V{sub th} exhibited a significant negative shift after UV exposure. The V{sub th} instability caused by UV illumination is attributed to the positive charge trapping in the dielectric layer and/or at the channel/dielectric interface. The illuminated devices showed a slow recovery in threshold voltage without external bias. However, an instant recovery can be achieved by the application of positive gate pulses, which is due to the elimination of the positive trapped charges as a result of the presence of a large amount of field-induced electrons in the interface region.

  5. High optical and switching performance electrochromic devices based on a zinc oxide nanowire with poly(methyl methacrylate) gel electrolytes

    SciTech Connect (OSTI)

    Chun, Young Tea; Chu, Daping; Neeves, Matthew; Placido, Frank; Smithwick, Quinn

    2014-11-10

    High performance electrochromic devices have been fabricated and demonstrated utilizing a solid polymer electrolyte and zinc oxide (ZnO) nanowire (NW) array counter electrode. The poly(methyl methacrylate) based polymer electrolyte was spin coated upon hydrothermally grown ZnO NW array counter electrodes, while electron beam evaporated NiO{sub x} thin films formed the working electrodes. Excellent optical contrast and switching speeds were observed in the fabricated devices with active areas of 2?cm{sup 2}, exhibiting an optical contrast of 73.11% at the wavelength of 470?nm, combined with a fast switching time of 0.2 s and 0.4 s for bleaching and coloration, respectively.

  6. Low power zinc-oxide based charge trapping memory with embedded silicon nanoparticles via poole-frenkel hole emission

    SciTech Connect (OSTI)

    El-Atab, Nazek; Nayfeh, Ammar; Ozcan, Ayse; Alkis, Sabri; Okyay, Ali K.; Department of Electrical and Electronics Engineering, Bilkent University, 06800 Ankara

    2014-01-06

    A low power zinc-oxide (ZnO) charge trapping memory with embedded silicon (Si) nanoparticles is demonstrated. The charge trapping layer is formed by spin coating 2?nm silicon nanoparticles between Atomic Layer Deposited ZnO steps. The threshold voltage shift (?V{sub t}) vs. programming voltage is studied with and without the silicon nanoparticles. Applying ?1?V for 5?s at the gate of the memory with nanoparticles results in a ?V{sub t} of 3.4?V, and the memory window can be up to 8?V with an excellent retention characteristic (>10 yr). Without nanoparticles, at ?1?V programming voltage, the ?V{sub t} is negligible. In order to get ?V{sub t} of 3.4?V without nanoparticles, programming voltage in excess of 10?V is required. The negative voltage on the gate programs the memory indicating that holes are being trapped in the charge trapping layer. In addition, at 1?V the electric field across the 3.6?nm tunnel oxide is calculated to be 0.36 MV/cm, which is too small for significant tunneling. Moreover, the ?V{sub t} vs. electric field across the tunnel oxide shows square root dependence at low fields (E??2.7 MV/cm). This indicates that Poole-Frenkel Effect is the main mechanism for holes emission at low fields and Phonon Assisted Tunneling at higher fields.

  7. pH effect on structural and optical properties of nanostructured zinc oxide thin films

    SciTech Connect (OSTI)

    Munef, R. A.

    2015-03-30

    ZnO nanostructures were Deposited on Objekttrager glasses for various pH values by chemical bath deposition method using Zn (NO3)2·6H2O (zinc nitrate hexahydrate) solution at 75°C reaction temperature without any posterior treatments. The ZnO nanostructures obtained were characterized by X-ray Diffraction (XRD, UV). The structure was hexagonal and it was found that some peaks disappear with various pH values. The grain sizes of ZnO films increases from 22-to-29nm with increasing pH. The transmission of the films was (85-95%)

  8. Band gap narrowing in zinc oxide-based semiconductor thin films

    SciTech Connect (OSTI)

    Kumar, Jitendra E-mail: akrsri@gmail.com; Kumar Srivastava, Amit E-mail: akrsri@gmail.com

    2014-04-07

    A simple expression is proposed for the band gap narrowing (or shrinkage) in semiconductors using optical absorption measurements of spin coated 1 at. % Ga-doped ZnO (with additional 0–1.5 at. % zinc species) thin films as ΔE{sub BGN} = Bn{sup 1/3} [1 − (n{sub c}/n){sup 1/3}], where B is the fitting parameter, n is carrier concentration, and n{sub c} is the critical density required for shrinkage onset. Its uniqueness lies in not only describing variation of ΔE{sub BGN} correctly but also allowing deduction of n{sub c} automatically for several M-doped ZnO (M: Ga, Al, In, B, Mo) systems. The physical significance of the term [1 − (n{sub c}/n){sup 1/3}] is discussed in terms of carrier separation.

  9. Regeneration of zinc chloride hydrocracking catalyst

    DOE Patents [OSTI]

    Zielke, Clyde W.

    1979-01-01

    Improved rate of recovery of zinc values from the solids which are carried over by the effluent vapors from the oxidative vapor phase regeneration of spent zinc chloride catalyst is achieved by treatment of the solids with both hydrogen chloride and calcium chloride to selectively and rapidly recover the zinc values as zinc chloride.

  10. Electrical and gas sensing properties of self-aligned copper-doped zinc oxide nanoparticles

    SciTech Connect (OSTI)

    Sonawane, Yogesh S.; Kanade, K.G.; Kale, B.B. Aiyer, R.C.

    2008-10-02

    Electrical and gas sensing properties of nanocrystalline ZnO:Cu, having Cu X wt% (X = 0.0, 0.5, 1.0, and 1.5) in ZnO, in the form of pellet were investigated. Copper chloride and zinc acetate were used as precursors along with oxalic acid as a precipitating reagent in methanol. Material characterization was done by X-ray diffraction (XRD), scanning electron microscopy (SEM), field emission scanning electron microscopy (FE-SEM) and inductive coupled plasma with optical emission spectrometry (ICP-OES). FE-SEM showed the self-aligned Cu-doped ZnO nano-clusters with particles in the range of 40-45 nm. The doping of 0.5% of copper changes the electrical conductivity by an order of magnitude whereas the temperature coefficient of resistance (TCR) reduces with increase in copper wt% in ZnO. The material has shown an excellent sensitivity for the H{sub 2}, LPG and CO gases with limited temperature selectivity through the optimized operating temperature of 130, 190 and 220 deg. C for H{sub 2}, LPG and CO gases, respectively at 625 ppm gas concentration. The %SF was observed to be 1460 for H{sub 2} at 1% Cu doping whereas the 0.5% Cu doping offered %SF of 950 and 520 for CO and LPG, respectively. The response and recovery time was found to be 6 to 8 s and 16 s, respectively.

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

    DOE Patents [OSTI]

    Ray, Siba P.; Weirauch, Jr., Douglas A.; Liu, Xinghua

    2002-01-01

    An inert anode for the electrolytic production of metals such as aluminum is disclosed. The inert anode includes a ceramic oxide material preferably made from NiO, Fe.sub.2 O.sub.3 and ZnO. The inert anode composition may comprise the following mole fractions of NiO, Fe.sub.2 O.sub.3 and ZnO: 0.2 to 0.99 NiO; 0.0001 to 0.8 Fe.sub.2 O.sub.3 ; and 0.0001 to 0.3 ZnO. The inert anode may optionally include other oxides and/or at least one metal phase, such as Cu, Ag, Pd, Pt, Au, Rh, Ru, Ir and/or Os. The Ni--Fe--Co--O ceramic material exhibits very low solubility in Hall cell baths used to produce aluminum.

  12. Ohmic contact formation process on low n-type gallium arsenide (GaAs) using indium gallium zinc oxide (IGZO)

    SciTech Connect (OSTI)

    Yang, Seong-Uk; Jung, Woo-Shik; Lee, In-Yeal; Jung, Hyun-Wook; Kim, Gil-Ho; Park, Jin-Hong

    2014-02-01

    Highlights: We propose a method to fabricate non-gold Ohmic contact on low n-type GaAs with IGZO. 0.15 A/cm{sup 2} on-current and 1.5 on/off-current ratio are achieved in the junction. InAs and InGaAs formed by this process decrease an electron barrier height. Traps generated by diffused O atoms also induce a trap-assisted tunneling phenomenon. - Abstract: Here, an excellent non-gold Ohmic contact on low n-type GaAs is demonstrated by using indium gallium zinc oxide and investigating through time of flight-secondary ion mass spectrometry, X-ray photoelectron spectroscopy, transmission electron microscopy, JV measurement, and H [enthalpy], S [entropy], Cp [heat capacity] chemistry simulation. In is diffused through GaAs during annealing and reacts with As, forming InAs and InGaAs phases with lower energy bandgap. As a result, it decreases the electron barrier height, eventually increasing the reverse current. In addition, traps generated by diffused O atoms induce a trap-assisted tunneling phenomenon, increasing generation current and subsequently the reverse current. Therefore, an excellent Ohmic contact with 0.15 A/cm{sup 2} on-current density and 1.5 on/off-current ratio is achieved on n-type GaAs.

  13. Method for the regeneration of spent molten zinc chloride

    DOE Patents [OSTI]

    Zielke, Clyde W.; Rosenhoover, William A.

    1981-01-01

    In a process for regenerating spent molten zinc chloride which has been used in the hydrocracking of coal or ash-containing polynuclear aromatic hydrocarbonaceous materials derived therefrom and which contains zinc chloride, zinc oxide, zinc oxide complexes and ash-containing carbonaceous residue, by incinerating the spent molten zinc chloride to vaporize the zinc chloride for subsequent condensation to produce a purified molten zinc chloride: an improvement comprising the use of clay in the incineration zone to suppress the vaporization of metals other than zinc. Optionally water is used in conjunction with the clay to further suppress the vaporization of metals other than zinc.

  14. Microstructure evolution of Al-doped zinc oxide and Sn-doped indium oxide deposited by radio-frequency magnetron sputtering: A comparison

    SciTech Connect (OSTI)

    Nie, Man; Bikowski, Andre; Ellmer, Klaus

    2015-04-21

    The microstructure and morphology evolution of Al-doped zinc oxide (AZO) and Sn-doped indium oxide (ITO) thin films on borosilicate glass substrates deposited by radio-frequency magnetron sputtering at room temperature (RT) and 300 °C were investigated by X-ray diffraction and atomic force microscopy (AFM). One-dimensional power spectral density (1DPSD) functions derived from the AFM profiles, which can be used to distinguish different growth mechanisms, were used to compare the microstructure scaling behavior of the thin films. The rms roughness R{sub q} evolves with film thickness as a power law, R{sub q} ∼ d{sub f}{sup β}, and different growth exponents β were found for AZO and ITO films. For AZO films, β of 1.47 and 0.56 are obtained for RT and 300 °C depositions, respectively, which are caused by the high compressive stress in the film at RT and relaxation of the stress at 300 °C. While for ITO films, β{sub 1} = 0.14 and β{sub 2} = 0.64 for RT, and β{sub 1} = 0.89 and β{sub 2} = 0.3 for 300 °C deposition are obtained, respectively, which is related to the strong competition between the surface diffusion and shadowing effect and/or grain growth. Electrical properties of both materials as a function of film thickness were also compared. By the modified Fuchs-Sondheimer model fitting of the electrical transport in both materials, different nucleation states are pointed out for both types of films.

  15. Dye-sensitized solar cell employing zinc oxide aggregates grown in the presence of lithium

    DOE Patents [OSTI]

    Zhang, Qifeng; Cao, Guozhong

    2013-10-15

    Provided are a novel ZnO dye-sensitized solar cell and method of fabricating the same. In one embodiment, deliberately added lithium ions are used to mediate the growth of ZnO aggregates. The use of lithium provides ZnO aggregates that have advantageous microstructure, morphology, crystallinity, and operational characteristics. Employing lithium during aggregate synthesis results in a polydisperse collection of ZnO aggregates favorable for porosity and light scattering. The resulting nanocrystallites forming the aggregates have improved crystallinity and more favorable facets for dye molecule absorption. The lithium synthesis improves the surface stability of ZnO in acidic dyes. The procedures developed and disclosed herein also help ensure the formation of an aggregate film that has a high homogeneity of thickness, a high packing density, a high specific surface area, and good electrical contact between the film and the fluorine-doped tin oxide electrode and among the aggregate particles.

  16. Method of removing hydrogen sulfide from gases utilizing a zinc oxide sorbent and regenerating the sorbent

    DOE Patents [OSTI]

    Jalan, Vinod M.; Frost, David G.

    1984-01-01

    A spent solid sorbent resulting from the removal of hydrogen sulfide from a fuel gas flow is regenerated with a steam-air mixture. The mixture of steam and air may also include additional nitrogen or carbon dioxide. The gas mixture contacts the spent sorbent containing metal sulfide at a temperature above 500.degree. C. to regenerate the sulfide to metal oxide or carbonate. Various metal species including the period four transition metals and the lanthanides are suitable sorbents that may be regenerated by this method. In addition, the introduction of carbon dioxide gas permits carbonates such as those of strontium, barium and calcium to be regenerated. The steam permits regeneration of spent sorbent without formation of metal sulfate. Moreover, the regeneration will proceed with low oxygen concentrations and will occur without the increase in temperature to minimize the risk of sintering and densification of the sorbent.

  17. Effects of humidity during formation of zinc oxide electron contact layers from a diethylzinc precursor solution

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

    Mauger, Scott A.; Steirer, K. Xerxes; Boe, Jonas; Ostrowski, David P.; Olson, Dana C.; Hammond, Scott R.

    2016-01-19

    Here, this work focuses on the role of humidity in the formation of ZnO thin films from a reactive diethylzinc precursor solution for use as the electron contact layer (ECL) in organic photovoltaic (OPV) devices. This method is well suited for flexible devices because the films are annealed at 120 °C, making the process compatible with polymer substrates. ZnO films were prepared by spin coating and annealing at different relative humidity (RH) levels. It is found that RH during coating and annealing affects the chemical and physical properties of the ZnO films. Using x-ray photoelectron spectroscopy it is found thatmore » increasing RH during the formation steps produces a more stoichiometric oxide and a higher Zn/O ratio. Spectroscopic ellipsometry data shows a small decrease in the optical band gap with increased humidity, consistent with a more stoichiometric oxide. Kelvin probe measurements show that increased RH during formation results in a larger work function (i.e. further from vacuum). Consistent with these data, but counter to what might be expected, when these ZnO films are used as ECLs in OPV devices those with ZnO ECLs processed in low RH (less stoichiometric) had higher power conversion efficiency than those with high-RH processed ZnO due to improved open-circuit voltage. The increase in open-circuit voltage with decreasing humidity was observed with two different donor polymers and fullerene acceptors, which shows the trend is due to changes in ZnO. The observed changes in open-circuit voltage follow the same trend as the ZnO work function indicating that the increase in open-circuit voltage with decreasing humidity is the result of improved energetics at the interface between the bulk-heterojunction and the ZnO layer due to a vacuum level shift.« less

  18. Real space pseudopotential calculations for size trends in Ga- and Al-doped zinc oxide nanocrystals with wurtzite and zincblende structures

    SciTech Connect (OSTI)

    Bobbitt, N. Scott; Kim, Minjung; Sai, Na; Marom, Noa; Chelikowsky, James R.

    2014-09-07

    Zinc oxide is often used as a popular inexpensive transparent conducting oxide. Here, we employ density functional theory and local density approximation to examine the effects of quantum confinement in doped nanocrystals of this material. Specifically, we examine the addition of Ga and Al dopants to ZnO nanocrystals on the order of 1.0 nm. We find that the inclusion of these dopants is energetically less favorable in smaller particles and that the electron binding energy, which is associated with the dopant activation, decreases with the nanocrystal size. We find that the introduction of impurities does not alter significantly the Kohn-Sham eigenspectrum for small nanocrystals of ZnO. The added electron occupies the lowest existing state, i.e., no new bound state is introduced in the gap. We verify this assertion with hybrid functional calculations.

  19. Vaporization of zinc from scrap

    SciTech Connect (OSTI)

    Ozturk, B.; Fruehan, R.J.

    1996-12-31

    The rate of zinc vaporization from galvanized scrap was measured using a thermogravimetric apparatus along with chemical analysis. It is found that the rate of zinc vaporization is very fast in nitrogen and carbon monoxide atmospheres at temperatures higher than 950 C. At lower temperature rate decreases with decreasing temperature and is controlled by the gas phase mass transport. The simultaneous oxidation and vaporization of zinc occurs when the samples were heated in carbon dioxide and air. The current experimental results indicate that almost all of the zinc from scrap vaporizes during the heating process in a very short period of time after the temperature reaches above 850 C.

  20. Zinc titanate sorbents

    DOE Patents [OSTI]

    Gupta, R.P.; Gangwal, S.K.; Jain, S.C.

    1998-02-03

    The present invention provides a zinc titanate sorbent material useful in desulfurization applications. The zinc titanate material is in the form of generally spherical particles of substantially uniform chemical distribution. The sorbent material is capable of absorbing sulfur compounds from a gaseous feed in an amount of at least about 15 weight percent based on the weight of the sorbent. The sorbent material is prepared by a process including: (a) forming a zinc oxide/titanium dioxide dry blend, (b) preparing a substantially uniform aqueous slurry comprising the zinc oxide/titanium dioxide dry blend, organic binder, and at least about 1 weight percent inorganic binder based on the solids weight of the slurry, (c) spray drying the slurry to produce substantially spherical particles, and (d) calcining the particles at a temperature of between about 750 to about 950 C. The dry blend is formed by mixing between about 0.5 to about 2 parts zinc oxide having a median particle size of less than about 0.5 microns, and about 1 part titanium dioxide having a median particle size of less than about 1 micron. The slurry contains substantially no free silica and may be prepared by the process including (1) preparing an aqueous solution of organic binder, (2) adding the dry blend to the aqueous solution of organic binder, and (3) adding the inorganic binder to the solution of organic binder, and blend. Additional reagents, such as a surfactant, may also be incorporated into the sorbent material. The present invention also provides a process for desulfurizing a gaseous stream. The process includes passing a gaseous stream through a reactor containing an attrition resistant zinc titanate sorbent material of the present invention.

  1. Zinc titanate sorbents

    DOE Patents [OSTI]

    Gupta, Raghubir P.; Gangwal, Santosh K.; Jain, Suresh C.

    1998-01-01

    The present invention provides a zinc titanate sorbent material useful in desulfurization applications. The zinc titanate material is in the form of generally spherical particles of substantially uniform chemical distribution. The sorbent material is capable of absorbing sulfur compounds from a gaseous feed in an amount of at least about 15 weight percent based on the weight of the sorbent. The sorbent material is prepared by a process including: (a) forming a zinc oxide/titanium dioxide dry blend, (b) preparing a substantially uniform aqueous slurry comprising the zinc oxide/titanium dioxide dry blend, organic binder, and at least about 1 weight percent inorganic binder based on the solids weight of the slurry, (c) spray drying the slurry to produce substantially spherical particles, and (d) calcining the particles at a temperature of between about 750.degree. C. to about 950.degree. C. The dry blend is formed by mixing between about 0.5 to about 2 parts zinc oxide having a median particle size of less than about 0.5 .mu., and about 1 part titanium dioxide having a median particle size of less than about 1 .mu.. The slurry contains substantially no free silica and may be prepared by the process including (1) preparing an aqueous solution of organic binder, (2) adding the dry blend to the aqueous solution of organic binder, and (3) adding the inorganic binder to the solution of organic binder, and blend. Additional reagents, such as a surfactant, may also be incorporated into the sorbent material. The present invention also provides a process for desulfurizing a gaseous stream. The process includes passing a gaseous stream through a reactor containing an attrition resistant zinc titanate sorbent material of the present invention.

  2. Studies on supported metal oxide-oxide support interactions ...

    Office of Scientific and Technical Information (OSTI)

    Subject: 36 MATERIALS SCIENCE; 66 PHYSICS; CERIUM OXIDES; SURFACE PROPERTIES; ALUMINIUM OXIDES; COPPER OXIDES; BINDING ENERGY; X-RAY DIFFRACTION; INFRARED SPECTRA; VALENCE; ZINC ...

  3. Stable photoluminescence of zinc oxide quantum dots in silica nanoparticles matrix prepared by the combined sol{endash}gel and spray drying method

    SciTech Connect (OSTI)

    Mikrajuddin; Iskandar, F.; Okuyama, K.; Shi, F. G.

    2001-06-01

    A sol{endash}gel method was employed to produce a zinc oxide (ZnO) colloid consisting of ZnO nanocrystalline particles with an average diameter of {similar_to}3 nm, and subsequently mixed with a silica (SiO{sub 2}) colloid. The mixture was finally spray dried to form a powder nanocomposite. It was found that the green photoluminescence (PL) exhibited by the composite was very stable: the intensity, position, and shape do not change even after being aged over 30 days. Thus, the ZnO/SiO{sub 2} nanocomposite has a much improved PL stability over ZnO colloids, which is often found to undergo a significant redshift even after aging over a few days. Our results are expected to have significant technological implications. {copyright} 2001 American Institute of Physics.

  4. Effects of low-temperature (120 °C) annealing on the carrier concentration and trap density in amorphous indium gallium zinc oxide thin film transistors

    SciTech Connect (OSTI)

    Kim, Jae-sung; Piao, Mingxing; Jang, Ho-Kyun; Kim, Gyu-Tae; Oh, Byung Su; Joo, Min-Kyu; Ahn, Seung-Eon

    2014-12-28

    We report an investigation of the effects of low-temperature annealing on the electrical properties of amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors (TFTs). X-ray photoelectron spectroscopy was used to characterize the charge carrier concentration, which is related to the density of oxygen vacancies. The field-effect mobility was found to decrease as a function of the charge carrier concentration, owing to the presence of band-tail states. By employing the transmission line method, we show that the contact resistance did not significantly contribute to the changes in device performance after annealing. In addition, using low-frequency noise analyses, we found that the trap density decreased by a factor of 10 following annealing at 120 °C. The switching operation and on/off ratio of the a-IGZO TFTs improved considerably after low-temperature annealing.

  5. Realization of write-once-read-many-times memory device with O{sub 2} plasma-treated indium gallium zinc oxide thin film

    SciTech Connect (OSTI)

    Liu, P. Chen, T. P. Li, X. D.; Wong, J. I.; Liu, Z.; Liu, Y.; Leong, K. C.

    2014-01-20

    A write-once-read-many-times (WORM) memory devices based on O{sub 2} plasma-treated indium gallium zinc oxide (IGZO) thin films has been demonstrated. The device has a simple Al/IGZO/Al structure. The device has a normally OFF state with a very high resistance (e.g., the resistance at 2?V is ?10{sup 9} ? for a device with the radius of 50??m) as a result of the O{sub 2} plasma treatment on the IGZO thin films. The device could be switched to an ON state with a low resistance (e.g., the resistance at 2?V is ?10{sup 3} ? for the radius of 50??m) by applying a voltage pulse (e.g., 10?V/1??s). The WORM device has good data-retention and reading-endurance capabilities.

  6. Regeneration of zinc halide catalyst used in the hydrocracking of polynuclear hydrocarbons

    DOE Patents [OSTI]

    Gorin, Everett

    1978-01-01

    Improved recovery of spent molten zinc halide hydro-cracking catalyst is achieved in the oxidative vapor phase regeneration thereof by selective treatment of the zinc oxide carried over by the effluent vapors from the regeneration zone with hydrogen halide gas under conditions favoring the reaction of the zinc oxide with the hydrogen halide, whereby regenerated zinc halide is recovered in a solids-free state with little loss of zinc values.

  7. Highly transparent conductive electrode with ultra-low HAZE by grain boundary modification of aqueous solution fabricated alumina-doped zinc oxide nanocrystals

    SciTech Connect (OSTI)

    Nian, Qiong; Cheng, Gary J.; Callahan, Michael; Bailey, John; Look, David; Efstathiadis, Harry

    2015-06-01

    Commercial production of transparent conducting oxide (TCO) polycrystalline films requires high electrical conductivity with minimal degradation in optical transparency. Aqueous solution deposited TCO films would reduce production costs of TCO films but suffer from low electrical mobility, which severely degrades both electrical conductivity and optical transparency in the visible spectrum. Here, we demonstrated that grain boundary modification by ultra-violet laser crystallization (UVLC) of solution deposited aluminium-doped zinc oxide (AZO) nanocrystals results in high Hall mobility, with a corresponding dramatic improvement in AZO electrical conductance. The AZO films after laser irradiation exhibit electrical mobility up to 18.1 cm{sup 2} V{sup −1} s{sup −1} with corresponding electrical resistivity and sheet resistances as low as 1 × 10{sup −3} Ω cm and 75 Ω/sq, respectively. The high mobility also enabled a high transmittance (T) of 88%-96% at 550 nm for the UVLC films. In addition, HAZE measurement shows AZO film scattering transmittance as low as 1.8%, which is superior over most other solution deposited transparent electrode alternatives such as silver nanowires. Thus, AZO films produced by the UVLC technique have a combined figure of merit for electrical conductivity, optical transparency, and optical HAZE higher than other solution based deposition techniques and comparable to vacuumed based deposition methods.

  8. Influence of growth temperature on electrical, optical, and plasmonic properties of aluminum:zinc oxide films grown by radio frequency magnetron sputtering

    SciTech Connect (OSTI)

    Dondapati, Hareesh; Santiago, Kevin; Pradhan, A. K.

    2013-10-14

    We have investigated the responsible mechanism for the observation of metallic conductivity at room temperature and metal-semiconductor transition (MST) at lower temperatures for aluminum-doped zinc oxide (AZO) films. AZO films were grown on glass substrates by radio-frequency magnetron sputtering with varying substrate temperatures (T{sub s}). The films were found to be crystalline with the electrical resistivity close to 1.1 × 10{sup −3} Ω cm and transmittance more than 85% in the visible region. The saturated optical band gap of 3.76 eV was observed for the sample grown at T{sub s} of 400 °C, however, a slight decrease in the bandgap was noticed above 400 °C, which can be explained by Burstein–Moss effect. Temperature dependent resistivity measurements of these highly conducting and transparent films showed a MST at ∼110 K. The observed metal-like and metal-semiconductor transitions are explained by taking into account the Mott phase transition and localization effects due to defects. All AZO films demonstrate crossover in permittivity from positive to negative and low loss in the near-infrared region, illustrating its applications for plasmonic metamaterials, including waveguides for near infrared telecommunication region. Based on the results presented in this study, the low electrical resistivity and high optical transmittance of AZO films suggested a possibility for the application in the flexible electronic devices, such as transparent conducting oxide film on LEDs, solar cells, and touch panels.

  9. Recovery of iron, carbon and zinc from steel plant waste oxides using the AISI-DOE postcombustion smelting technology

    SciTech Connect (OSTI)

    Sarma, B.; Downing, K.B.; Aukrust, E.

    1996-09-01

    This report describes a process to recover steel plant waste oxides to be used in the production of hot metal. The process flowsheet used at the pilot plant. Coal/coke breeze and iron ore pellets/waste oxides are charged into the smelting reactor. The waste oxides are either agglomerated into briquettes (1 inch) using a binder or micro-agglomerated into pellets (1/4 inch) without the use of a binder. The iron oxides dissolve in the slag and are reduced by carbon to produce molten iron. The gangue oxides present in the raw materials report to the slag. Coal charged to the smelter is both the fuel as well as the reductant. Carbon present in the waste oxides is also used as the fuel/reductant resulting in a decrease in the coal requirement. Oxygen is top blown through a central, water-cooled, dual circuit lance. Nitrogen is injected through tuyeres at the bottom of the reactor for stirring purposes. The hot metal and slag produced in the smelting reactor are tapped at regular intervals through a single taphole using a mudgun and drill system. The energy requirements of the process are provided by (i) the combustion of carbon to carbon monoxide, referred to as primary combustion and (ii) the combustion of CO and H{sub 2} to CO{sub 2} and H{sub 2}O, known as postcombustion.

  10. Effect of different processes and Ti/Zn molar ratios on the structure, morphology, and enhanced photoelectrochemical and photocatalytic performance of Ti3+ self-doped titanium–zinc hybrid oxides

    SciTech Connect (OSTI)

    Fu, Rongrong; Wang, Qingyao; Gao, shanmin; Wang, Zeyan; Huang, Baibiao; Dai, Ying; Lu, Jun

    2015-07-01

    Ti3+ self-doped titanium–zinc hybrid oxides with different phase compositions and morphologies were successfully synthesized using Zn powder as the reductant and Zn source by a chemical-reduction precipitation method with subsequent thermal treatment. The fabricated Ti3+ self-doped TiO2(A)/TiO2(R), TiO2(A)/TiO2(R)/ZnTiO3, and TiO2(A)/ZnO heterojunctions were characterized by X-ray diffraction, transmission electron microscopy, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, and UV–Vis diffuse reflectance spectroscopy. The effects of various Ti/Zn molar ratios and preparation processes on the structural, morphological, optical, photocurrent and photocatalytic properties of the resultant samples were investigated systematically. Results reveal that Ti3+ self-doping enhances the photoabsorption capability of titanium–zinc hybrid oxides in the visible-light region. Moreover, different processes and Ti/Zn molar ratios play great influences on the structure, morphology, optical, photocurrent and photocatalytic properties of the final products. Ti3+ self-doped titanium–zinc hybrid oxides exhibit excellent photocurrent and photocatalytic activity than pure TiO2 and ZnTiO3 under visible-light irradiation (λ ≥ 400 nm). The most active Ti3+ self-doped titanium–zinc hybrid oxides photoanode presents significantly improved water splitting performance. The synergistic effect between the Ti3+ self-doped and heterojunctions is responsible for the enhanced performance of these materials.

  11. Attrition resistant, zinc titanate-containing, reduced sulfur sorbents and methods of use thereof

    DOE Patents [OSTI]

    Vierheilig, Albert A.; Gupta, Raghubir P.; Turk, Brian S.

    2006-06-27

    Reduced sulfur gas species (e.g., H.sub.2S, COS and CS.sub.2) are removed from a gas stream by compositions wherein a zinc titanate ingredient is associated with a metal oxide-aluminate phase material in the same particle species. Nonlimiting examples of metal oxides comprising the compositions include magnesium oxide, zinc oxide, calcium oxide, nickel oxide, etc.

  12. Plasmonic Three-Dimensional Transparent Conductor Based on Al-Doped Zinc Oxide-Coated Nanostructured Glass Using Atomic Layer Deposition

    SciTech Connect (OSTI)

    Malek, Gary A.; Aytug, Tolga; Liu, Qingfeng; Wu, Judy

    2015-04-02

    Transparent nanostructured glass coatings, fabricated on glass substrates, with a unique three-dimensional (3D) architecture were utilized as the foundation for the design of plasmonic 3D transparent conductors. Transformation of the non-conducting 3D structure to a conducting 3D network was accomplished through atomic layer deposition of aluminum-doped zinc oxide (AZO). After AZO growth, gold nanoparticles (AuNPs) were deposited by electronbeam evaporation to enhance light trapping and decrease the overall sheet resistance. Field emission scanning electron microscopy and atomic force microcopy images revealed the highly porous, nanostructured morphology of the AZO coated glass surface along with the in-plane dimensions of the deposited AuNPs. Sheet resistance measurements conducted on the coated samples verified that the electrical properties of the 3D network are comparable to that of the untextured two-dimensional AZO coated glass substrates. In addition, transmittance measurements of the glass samples coated with various AZO thicknesses showed preservation of the highly transparent nature of each sample, while the AuNPs demonstrated enhanced light scattering as well as light-trapping capability.

  13. Microbundles of zinc oxide nanorods: Assembly in ionic liquid [EMIM]{sup +}[BF{sub 4}]{sup -}, photoluminescence and photocatalytic properties

    SciTech Connect (OSTI)

    Wang Li; Xu Shenzhi; Li Huijun; Chang Lixian; Zhisu; Zeng Minghua; Wang Lina; Huang Yineng

    2011-03-15

    A simple, efficient and low-temperature approach for the assembly of hierarchical Zinc oxide (ZnO) microstructures in ionic liquid [EMIM]{sup +}[BF{sub 4}]{sup -} is reported. The as-obtained ZnO superstructures are composed of microbundles of nanorods from the center points, with the diameter and length in the range of 100-150 nm and 2-4 {mu}m, which have been characterized by X-ray diffraction, scanning and transmission electron microscopy, and photoluminescence spectroscopy. The ZnO microstructures exhibit significant defect-related green-yellow emission and high photodegradation of dye Methyl Orange (5x10{sup -5} mol/L) under UV excitation within 80 min. -- Graphical abstract: Easy formation of microbundles of ZnO nanorods were accomplished in low temperature with [EMIM]{sup +}[BF{sub 4}]{sup -} (1-ethyl-3-methylimidazolium tetrafluoroborate) ionic liquid, which exhibit significant green-yellow photoluminescence property and high photodegradation of Methyl Orange dye. Display Omitted Research highlights: {yields} Ionic liquid assisted solid-state route was introduced into synthesis of ZnO nanorods. {yields} The distinctive microbundles ZnO nanorod assembles was evidenced by SEM and TEM. {yields} ZnO nano-material exhibited high efficiency in photodegradation of Methyl Orange.

  14. Plasmonic Three-Dimensional Transparent Conductor Based on Al-Doped Zinc Oxide-Coated Nanostructured Glass Using Atomic Layer Deposition

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

    Malek, Gary A.; Aytug, Tolga; Liu, Qingfeng; Wu, Judy

    2015-04-02

    Transparent nanostructured glass coatings, fabricated on glass substrates, with a unique three-dimensional (3D) architecture were utilized as the foundation for the design of plasmonic 3D transparent conductors. Transformation of the non-conducting 3D structure to a conducting 3D network was accomplished through atomic layer deposition of aluminum-doped zinc oxide (AZO). After AZO growth, gold nanoparticles (AuNPs) were deposited by electronbeam evaporation to enhance light trapping and decrease the overall sheet resistance. Field emission scanning electron microscopy and atomic force microcopy images revealed the highly porous, nanostructured morphology of the AZO coated glass surface along with the in-plane dimensions of the depositedmore » AuNPs. Sheet resistance measurements conducted on the coated samples verified that the electrical properties of the 3D network are comparable to that of the untextured two-dimensional AZO coated glass substrates. In addition, transmittance measurements of the glass samples coated with various AZO thicknesses showed preservation of the highly transparent nature of each sample, while the AuNPs demonstrated enhanced light scattering as well as light-trapping capability.« less

  15. The effect of the solution flow rate on the properties of zinc oxide (ZnO) thin films deposited by ultrasonic spray

    SciTech Connect (OSTI)

    Attaf, A. Benkhetta, Y.; Saidi, H.; Bouhdjar, A.; Bendjedidi, H.; Nouadji, M.; Lehraki, N.

    2015-03-30

    In this work, we used a system based on ultrasonic spray pyrolysis technique. By witch, we have deposited thin films of zinc oxide (ZnO) with the variation of solution flow rate from 50 ml / h to 150 ml / h, and set other parameters such as the concentration of the solution, the deposition time, substrate temperature and the nozzel -substrate distance. In order to study the influence of the solution flow rate on the properties of the films produced, we have several characterization techniques such as X-ray diffraction to determine the films structure, the scanning electron microscopy SEM for the morphology of the surfaces, EDS spectroscopy for the chemical composition, UV-Visible-Nir spectroscopy for determination the optical proprieties of thin films.The experimental results show that: the films have hexagonal structure at the type (wurtzite), the average size of grains varies from 20.11 to 32.45 nm, the transmittance of the films equals 80% in visible rang and the band gap is varied between 3.274 and 3.282 eV, when the solution flow rate increases from 50 to 150 ml/h.

  16. The silicon/zinc oxide interface in amorphous silicon-based thin-film solar cells: Understanding an empirically optimized contact

    SciTech Connect (OSTI)

    Gerlach, D.; Wilks, R. G.; Wimmer, M.; Felix, R.; Gorgoi, M.; Lips, K.; Rech, B.; Wippler, D.; Mueck, A.; Meier, M.; Huepkes, J.; Lozac'h, M.; Ueda, S.; Sumiya, M.; Yoshikawa, H.; Kobayashi, K.; Baer, M.

    2013-07-08

    The electronic structure of the interface between the boron-doped oxygenated amorphous silicon 'window layer' (a-SiO{sub x}:H(B)) and aluminum-doped zinc oxide (ZnO:Al) was investigated using hard x-ray photoelectron spectroscopy and compared to that of the boron-doped microcrystalline silicon ({mu}c-Si:H(B))/ZnO:Al interface. The corresponding valence band offsets have been determined to be (-2.87 {+-} 0.27) eV and (-3.37 {+-} 0.27) eV, respectively. A lower tunnel junction barrier height at the {mu}c-Si:H(B)/ZnO:Al interface compared to that at the a-SiO{sub x}:H(B)/ZnO:Al interface is found and linked to the higher device performances in cells where a {mu}c-Si:H(B) buffer between the a-Si:H p-i-n absorber stack and the ZnO:Al contact is employed.

  17. Zinc oxide nanoparticles induce migration and adhesion of monocytes to endothelial cells and accelerate foam cell formation

    SciTech Connect (OSTI)

    Suzuki, Yuka; Tada-Oikawa, Saeko; Ichihara, Gaku; Yabata, Masayuki; Izuoka, Kiyora; Suzuki, Masako; Sakai, Kiyoshi; Ichihara, Sahoko

    2014-07-01

    Metal oxide nanoparticles are widely used in industry, cosmetics, and biomedicine. However, the effects of exposure to these nanoparticles on the cardiovascular system remain unknown. The present study investigated the effects of nanosized TiO{sub 2} and ZnO particles on the migration and adhesion of monocytes, which are essential processes in atherosclerogenesis, using an in vitro set-up of human umbilical vein endothelial cells (HUVECs) and human monocytic leukemia cells (THP-1). We also examined the effects of exposure to nanosized metal oxide particles on macrophage cholesterol uptake and foam cell formation. The 16-hour exposure to ZnO particles increased the level of monocyte chemotactic protein-1 (MCP-1) and induced the migration of THP-1 monocyte mediated by increased MCP-1. Exposure to ZnO particles also induced adhesion of THP-1 cells to HUVECs. Moreover, exposure to ZnO particles, but not TiO{sub 2} particles, upregulated the expression of membrane scavenger receptors of modified LDL and increased cholesterol uptake in THP-1 monocytes/macrophages. In the present study, we found that exposure to ZnO particles increased macrophage cholesterol uptake, which was mediated by an upregulation of membrane scavenger receptors of modified LDL. These results suggest that nanosized ZnO particles could potentially enhance atherosclerogenesis and accelerate foam cell formation. - Highlights: • Effects of metal oxide nanoparticles on foam cell formation were investigated. • Exposure to ZnO nanoparticles induced migration and adhesion of monocytes. • Exposure to ZnO nanoparticles increased macrophage cholesterol uptake. • Expression of membrane scavenger receptors of modified LDL was also increased. • These effects were not observed after exposure to TiO{sub 2} nanoparticles.

  18. Effect of top gate bias on photocurrent and negative bias illumination stress instability in dual gate amorphous indium-gallium-zinc oxide thin-film transistor

    SciTech Connect (OSTI)

    Lee, Eunji; Chowdhury, Md Delwar Hossain; Park, Min Sang; Jang, Jin

    2015-12-07

    We have studied the effect of top gate bias (V{sub TG}) on the generation of photocurrent and the decay of photocurrent for back channel etched inverted staggered dual gate structure amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film-transistors. Upon 5 min of exposure of 365 nm wavelength and 0.7 mW/cm{sup 2} intensity light with negative bottom gate bias, the maximum photocurrent increases from 3.29 to 322 pA with increasing the V{sub TG} from −15 to +15 V. By changing V{sub TG} from negative to positive, the Fermi level (E{sub F}) shifts toward conduction band edge (E{sub C}), which substantially controls the conversion of neutral vacancy to charged one (V{sub O} → V{sub O}{sup +}/V{sub O}{sup 2+} + e{sup −}/2e{sup −}), peroxide (O{sub 2}{sup 2−}) formation or conversion of ionized interstitial (O{sub i}{sup 2−}) to neutral interstitial (O{sub i}), thus electron concentration at conduction band. With increasing the exposure time, more carriers are generated, and thus, maximum photocurrent increases until being saturated. After negative bias illumination stress, the transfer curve shows −2.7 V shift at V{sub TG} = −15 V, which gradually decreases to −0.42 V shift at V{sub TG} = +15 V. It clearly reveals that the position of electron quasi-Fermi level controls the formation of donor defects (V{sub O}{sup +}/V{sub O}{sup 2+}/O{sub 2}{sup 2−}/O{sub i}) and/or hole trapping in the a-IGZO /interfaces.

  19. Zinc electrode with cement additive

    DOE Patents [OSTI]

    Charkey, Allen

    1982-06-01

    A zinc electrode having a cement additive, preferably, Portland Cement, distributed in the zinc active material.

  20. Attrition resistant, zinc titanate-containing, reduced sulfur sorbents

    DOE Patents [OSTI]

    Vierheilig, Albert A.; Gupta, Raghubir P.; Turk, Brian S.

    2004-11-02

    The disclosure is directed to sorbent compositions for removing reduced sulfur species (e.g., H.sub.2 S, COS and CS.sub.2) a feed stream. The sorbent is formed from a multi-phase composition including a zinc titanate phase and a zinc oxide-aluminate phase. The sorbent composition is substantially free of unreacted alumina.

  1. The solubility of zinc oxide in 0.03 m NaTr as a function of temperature, with in situ pH measurement

    SciTech Connect (OSTI)

    Benezeth, P.; Palmer, D.A.; Wesolowski, D.J.

    1999-05-01

    The solubility of zincite (ZnO) has been measured in noncomplexing solutions over a wide range of pH{sub m} (4--11), and temperature (75--200 C) at 0.03 mol/kg ionic strength in NaTr media (sodium trifluoromethanesulfonate, a noncomplexing 1:1 electrolyte), in a hydrogen electrode concentration cell (HECC), which provided continuous in situ measurement of hydrogen ion molality. Total zinc content was analyzed by atomic absorption using graphite furnace, flame, and inductively coupled plasma (ICP) spectrometers. The direction of approach to the equilibrium saturation state was varied to demonstrate that the system was reversible thermodynamically. Separate experiments were performed in alkaline solutions (0.03 mol/kg NaOH) at 25 and 50 C in polypropylene syringes, and between 50 and 290 C in a Teflon-lined pressure vessel. The aim of these experiments was to reach higher pH{sub m} (>8 depending on the temperature) to determine the thermodynamic properties of the negatively charged species, Zn(OH){sub 3}{sup {minus}}. A least-squares regression of the results obtained at this ionic strength was used to determine the molal solubility products (Q{sub sn}) of zincite. The solubility products (Q{sub sn}) were extrapolated to infinite dilution (K{sub sn}), permitting calculation of the thermodynamic properties of aqueous species of zinc for comparison with previous work.

  2. Additive agent for zinc alloy electrolyte and process

    SciTech Connect (OSTI)

    Bammel, B.D.

    1986-07-01

    An aqueous acidic electrolyte is described suitable for electrodepositing zinc alloys on a substrate comprising zinc ions and at least one additional metal ion selected from the group consisting nickel, cobalt, iron and mixtures thereof present in an amount sufficient to electrodeposit a zinc alloy, and, for providing improved grain-refinement and enhancing the codeposition of the alloying metals in the zinc alloy deposit. An effective amount of an additive agent consists of a bath-soluble anionic carboxylated polyoxyalkylene compound derived from the carboxylation of: (a) the polymerization of alkylene oxides selected from the group consisting of ethylene oxide, propylene oxide, glycidol, butylene oxide and mixtures thereof; and (b) the alkoxylation of mono and polyhydroxy compounds selected from the group consisting of hydroxyl containing alkyl, alkenyl, alkynyl, aryl, as well as mixtures thereof.

  3. Oxide

    SciTech Connect (OSTI)

    2014-07-15

    Oxide is a modular framework for feature extraction and analysis of executable files. Oxide is useful in a variety of reverse engineering and categorization tasks relating to executable content.

  4. Improved zinc electrode and rechargeable zinc-air battery

    DOE Patents [OSTI]

    Ross, P.N. Jr.

    1988-06-21

    The invention comprises an improved rechargeable zinc-air cell/battery having recirculating alkaline electrolyte and a zinc electrode comprising a porous foam support material which carries the active zinc electrode material. 5 figs.

  5. Zinc phosphate conversion coatings

    DOE Patents [OSTI]

    Sugama, T.

    1997-02-18

    Zinc phosphate conversion coatings for producing metals which exhibit enhanced corrosion prevention characteristics are prepared by the addition of a transition-metal-compound promoter comprising a manganese, iron, cobalt, nickel, or copper compound and an electrolyte such as polyacrylic acid, polymethacrylic acid, polyitaconic acid and poly-L-glutamic acid to a phosphating solution. These coatings are further improved by the incorporation of Fe ions. Thermal treatment of zinc phosphate coatings to generate {alpha}-phase anhydrous zinc phosphate improves the corrosion prevention qualities of the resulting coated metal. 33 figs.

  6. Zinc phosphate conversion coatings

    DOE Patents [OSTI]

    Sugama, Toshifumi

    1997-01-01

    Zinc phosphate conversion coatings for producing metals which exhibit enhanced corrosion prevention characteristics are prepared by the addition of a transition-metal-compound promoter comprising a manganese, iron, cobalt, nickel, or copper compound and an electrolyte such as polyacrylic acid, polymethacrylic acid, polyitaconic acid and poly-L-glutamic acid to a phosphating solution. These coatings are further improved by the incorporation of Fe ions. Thermal treatment of zinc phosphate coatings to generate .alpha.-phase anhydrous zinc phosphate improves the corrosion prevention qualities of the resulting coated metal.

  7. Zinc Speciation in Contaminated Sediments: Quantitative Determination...

    Office of Scientific and Technical Information (OSTI)

    Zinc Speciation in Contaminated Sediments: Quantitative Determination of Zinc Coordination by X-ray Absorption Spectroscopy Citation Details In-Document Search Title: Zinc ...

  8. Zinc electrode and rechargeable zinc-air battery

    DOE Patents [OSTI]

    Ross, Jr., Philip N.

    1989-01-01

    An improved zinc electrode is disclosed for a rechargeable zinc-air battery comprising an outer frame and a porous foam electrode support within the frame which is treated prior to the deposition of zinc thereon to inhibit the formation of zinc dendrites on the external surface thereof. The outer frame is provided with passageways for circulating an alkaline electrolyte through the treated zinc-coated porous foam. A novel rechargeable zinc-air battery system is also disclosed which utilizes the improved zinc electrode and further includes an alkaline electrolyte within said battery circulating through the passageways in the zinc electrode and an external electrolyte circulation means which has an electrolyte reservoir external to the battery case including filter means to filter solids out of the electrolyte as it circulates to the external reservoir and pump means for recirculating electrolyte from the external reservoir to the zinc electrode.

  9. Thin film cadmium telluride and zinc phosphide solar cells

    SciTech Connect (OSTI)

    Chu, T.

    1984-10-01

    This report describes research performed from June 1982 to October 1983 on the deposition of cadmium telluride films by direct combination of the cadmium and tellurium vapor on foreign substrates. Nearly stoichiometric p-type cadmium telluride films and arsenic-doped p-type films have been prepared reproducibly. Major efforts were directed to the deposition and characterization of heterojunction window materials, indium tin oxide, fluorine-doped tin oxide, cadmium oxide, and zinc oxide. A number of heterojunction solar cells were prepared, and the best thin-film ITO/CdTe solar cells had an AMl efficiency of about 7.2%. Zinc phosphide films were deposited on W/steel substrates by the reaction of zinc and phosphine in a hydrogen flow. Films without intentional doping had an electrical resistivity on the order of 10/sup 6/ ohm-cm, and this resistivity may be reduced to about 5 x 10/sup 4/ ohm-cm by adding hydrogen chloride or hydrogen bromide to the reaction mixture. Lower resistivity films were deposited by adding a controlled amount of silver nitrate solution on to the substrate surface. Major efforts were directed to the deposition of low-resistivity zinc selenide in order to prepare ZnSe/An/sub 3/P/sub 2/ heterojunction thin-film solar cells. However, zinc selenide films deposited by vacuum evaporation and chemical vapor deposition techniques were all of high resistivity.

  10. Photovoltaic cells employing zinc phosphide

    DOE Patents [OSTI]

    Barnett, Allen M.; Catalano, Anthony W.; Dalal, Vikram L.; Masi, James V.; Meakin, John D.; Hall, Robert B.

    1984-01-01

    A photovoltaic cell having a zinc phosphide absorber. The zinc phosphide can be a single or multiple crystal slice or a thin polycrystalline film. The cell can be a Schottky barrier, heterojunction or homojunction device. Methods for synthesizing and crystallizing zinc phosphide are disclosed as well as a method for forming thin films.

  11. Zinc deposition in acid electrolytes

    SciTech Connect (OSTI)

    McBreen, J.; Gannon, E.

    1981-01-01

    In the past decade, two aqueous zinc/halogen batteries, the zinc/chlorine, and the zinc/bromine systems, have been considered for load-leveling and vehicular applications. Even though considerable progress has been made in engineering these batteries, several problems related to the zinc electrode have yet to be solved. These are related to the growth of dendritic zinc and a maldistribution of the zinc deposit that can occur during cycling. Both problems are exacerbated by recharge of the battery after partial discharge of the zinc deposit. A survey of the literature indicates that a more desireable zinc morphology can be achieved by use of inorganic additives, fluorinated surfactants, and A-C modulation of the charging current. In this investigation, the deposition of zinc from zinc bromide and zinc chloride electrolytes was investigated under conditions that precluded dendrite growth. The techniques used were cyclic voltammetry, the potential step technique and scanning electron microscopy. The variables investigated were the substrate (zinc and dense graphite), electrolyte pH, inorganic additives (Pb/sup + +/ and Bi/sup 3 +/) and A-V modulation of the charging potential by superimposed square waves.

  12. Zinc sulfide liquefaction catalyst

    DOE Patents [OSTI]

    Garg, Diwakar

    1984-01-01

    A process for the liquefaction of carbonaceous material, such as coal, is set forth wherein coal is liquefied in a catalytic solvent refining reaction wherein an activated zinc sulfide catalyst is utilized which is activated by hydrogenation in a coal derived process solvent in the absence of coal.

  13. Durable zinc ferrite sorbent pellets for hot coal gas desulfurization

    DOE Patents [OSTI]

    Jha, Mahesh C.; Blandon, Antonio E.; Hepworth, Malcolm T.

    1988-01-01

    Durable, porous sulfur sorbents useful in removing hydrogen sulfide from hot coal gas are prepared by water pelletizing a mixture of fine zinc oxide and fine iron oxide with inorganic and organic binders and small amounts of activators such as sodium carbonate and molybdenite; the pellets are dried and then indurated at a high temperature, e.g., 1800.degree. C., for a time sufficient to produce crush-resistant pellets.

  14. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect (OSTI)

    Jha, M.C.; Berggren, M.H.

    1989-05-02

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  15. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect (OSTI)

    Jha, M.C.; Berggren, M.H.

    1988-11-14

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  16. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect (OSTI)

    Jha, M.C.; Berggren, M.H.

    1989-03-06

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  17. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect (OSTI)

    Jha, M.C.; Berggren, M.H.

    1988-08-19

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  18. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect (OSTI)

    Jha, M.C.; Baltich, L.K.; Berggren, M.H.

    1987-05-18

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  19. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect (OSTI)

    Jha, M.C.; Baltich, L.K.; Berggren, M.H.

    1987-08-28

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  20. Extracellular Proteins Promote Zinc Sulfide Aggregation

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

    National Laboratory analyzed biofilm samples rich in zinc sulfide and dominated by sulfate-reducing bacteria, which were collected from lead-zinc mine waters. The researchers...

  1. Aqueous Zinc Bromide Waste Solidification

    SciTech Connect (OSTI)

    Langton, C.A.

    2002-07-23

    The goal of this study was to select one or more commercially available aqueous sorbents to solidify the zinc bromide solution stored in C-Area, identify the polymer to zinc bromide solution ratio (waste loading) for the selected sorbents, and identify processing issues that require further testing in pilot-scale testing.

  2. EFFECT OF THERMAL PROCESSES ON COPPER-TIN ALLOYS FOR ZINC GETTERING

    SciTech Connect (OSTI)

    Korinko, P.; Golyski, M.

    2013-11-01

    A contamination mitigation plan was initiated to address the discovery of radioactive zinc‐65 in a glovebox. A near term solution was developed, installation of heated filters in the glovebox piping. This solution is effective at retaining the zinc in the currently contaminated area, but the gamma emitting contaminant is still present in a system designed for tritium beta. A project was initiated to develop a solution to contain the {sup 65}Zn in the furnace module. Copper and bronze (a Cu/Sn alloy) were found to be candidate materials to combine with zinc‐65 vapor, using thermodynamic calculations. A series of binary Cu/Sn alloys were developed (after determining that commercial alloys were unacceptable), that were found to be effective traps of zinc vapor. The task described in this report was undertaken to determine if the bronze substrates would retain their zinc gettering capability after being exposed to simulated extraction conditions with oxidizing and reducing gases. Pure copper and three bronze alloys were prepared, exposed to varying oxidation conditions from 250 to 450{degree}C, then exposed to varying reduction conditions in He-H{sub 2} from 250-450{degree}C, and finally exposed to zinc vapor at 350{degree}C for four hours. The samples were characterized using scanning electron microscopy, X-ray diffraction, differential thermal analysis, mass change, and visual observation. It was observed that the as fabricated samples and the reduced samples all retained their zinc gettering capacity while samples in the "as-oxidized" condition exhibited losses in zinc gettering capacity. Over the range of conditions tested, i.e., composition, oxidation temperature, and reduction temperature, no particular sample composition appeared better. Samples reduced at 350{degree}C exhibited the greatest zinc capacity, although there were some testing anomalies associated with these samples. This work clearly demonstrated that the zinc gettering was not adversely

  3. Zinc content of selected tissues and taste perception in rats fed zinc deficient and zinc adequate rations

    SciTech Connect (OSTI)

    Boeckner, L.S.; Kies, C.

    1986-03-05

    The objective of the study was to determine the effects of feeding zinc sufficient and zinc deficient rations on taste sensitivity and zinc contents of selected organs in rats. The 36 Sprague-Dawley male weanling rats were divided into 2 groups and fed zinc deficient or zinc adequate rations. The animals were subjected to 4 trial periods in which a choice of deionized distilled water or a solution of quinine sulfate at 1.28 x 10/sup -6/ was given. A randomized schedule for rat sacrifice was used. No differences were found between zinc deficient and zinc adequate rats in taste preference aversion scores for quinine sulfate in the first three trial periods; however, in the last trial period rats in the zinc sufficient group drank somewhat less water containing quinine sulfate as a percentage of total water consumption than did rats fed the zinc deficient ration. Significantly higher zinc contents of kidney, brain and parotid salivary glands were seen in zinc adequate rats compared to zinc deficient rats at the end of the study. However, liver and tongue zinc levels were lower for both groups at the close of the study than were those of rats sacrificed at the beginning of the study.

  4. Fluidizable zinc titanate materials with high chemical reactivity and attrition resistance

    DOE Patents [OSTI]

    Gupta, R.P.; Gangwal, S.K.; Jain, S.C.

    1993-10-19

    Highly durable and chemically reactive zinc titanate materials are prepared in a particle size range of 50 to 400 [mu]m suitable for a fluidized-bed reactor for removing reduced sulfur species in a gaseous form by granulating a mixture of fine zinc oxide and titanium oxide with inorganic and organic binders and by optional additions of small amounts of activators such as CoO and MoO[sub 3]; and then indurating it at 800 to 900 C for a time sufficient to produce attrition-resistant granules.

  5. LOW TEMPERATURE VOC COMBUSTION OVER MANGANESE, COBALT AND ZINC ALPO4 MOLECULAR SIEVES

    SciTech Connect (OSTI)

    Rosemarie Szostak

    2003-03-06

    The objective of this project was to prepare microporous aluminophosphates containing magnesium, manganese, cobalt and zinc (MeAPOs) and to evaluate their performance as oxidation catalysts for the removal of low levels of volatile organic compounds (VOCs) from gas streams. The tasks to be accomplished were as follows: (1) To develop reliable synthesis methods for metal aluminophosphates containing manganese, cobalt and zinc in their framework; (2) To characterize these materials for crystallinity, phase purity, the location and nature of the incorporated metal in the framework; and (3) To evaluate the materials for their catalytic activities in the oxidation of volatile organic environmental pollutants.

  6. Fluidizable zinc titanate materials with high chemical reactivity and attrition resistance

    DOE Patents [OSTI]

    Gupta, Raghubir P.; Gangwal, Santosh K.; Jain, Suresh C.

    1993-01-01

    Highly durable and chemically reactive zinc titanate materials are prepared in a particle size range of 50 to 400 .mu.m suitable for a fluidized-bed reactor for removing reduced sulfur species in a gaseous form by granulating a mixture of fine zinc oxide and titanium oxide with inorganic and organic binders and by optional additions of small amounts of activators such as CoO and MoO.sub.3 ; and then indurating it at 800.degree. to 900.degree. C. for a time sufficient to produce attrition-resistant granules.

  7. Extracellular Proteins Promote Zinc Sulfide Aggregation

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

    Extracellular Proteins Promote Zinc Sulfide Aggregation Extracellular Proteins Promote Zinc Sulfide Aggregation Print Wednesday, 26 September 2007 00:00 Researchers from the ALS, Berkeley Lab's National Center for Electron Microscopy (NCEM), and Lawrence Livermore National Laboratory analyzed biofilm samples rich in zinc sulfide and dominated by sulfate-reducing bacteria, which were collected from lead-zinc mine waters. The researchers were curious about the relationship of the organic material

  8. 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.

  9. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect (OSTI)

    Berggren, M.H.; Jha, M.C.

    1989-10-01

    AMAX Research Development Center (AMAX R D) investigated methods for enhancing the reactivity and durability of zinc ferrite desulfurization sorbents. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For this program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such as size, strength, and specific surface area during 10 cycles of sulfidation and oxidation. Two base case sorbents, a spherical pellet and a cylindrical extrude used in related METC-sponsored projects, were used to provide a basis for the aimed enhancement in durability and reactivity. Sorbent performance was judged on the basis of physical properties, single particle kinetic studies based on thermogravimetric (TGA) techniques, and multicycle bench-scale testing of sorbents. A sorbent grading system was utilized to quantify the characteristics of the new sorbents prepared during the program. Significant enhancements in both reactivity and durability were achieved for the spherical pellet shape over the base case formulation. Overall improvements to reactivity and durability were also made to the cylindrical extrude shape. The primary variables which were investigated during the program included iron oxide type, zinc oxide:iron oxide ratio, inorganic binder concentration, organic binder concentration, and induration conditions. The effects of some variables were small or inconclusive. Based on TGA studies and bench-scale tests, induration conditions were found to be very significant.

  10. Upper Los Alamos Canyon Cleanup

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

    Upper Los Alamos Canyon Cleanup Upper Los Alamos Canyon Cleanup The Upper Los Alamos Canyon Project involves cleaning up hazardous materials left over from some of the Laboratory's earliest activities. Contact Environmental Communication & Public Involvement P.O. Box 1663 MS M996 Los Alamos, NM 87545 (505) 667-0216 Email Located along Los Alamos Canyon from 7th Street to the Pajarito Ski Hill, the Upper Los Alamos Canyon Project involves examining sites in present and former Laboratory

  11. Analysis of Zinc 65 Contamination after Vacuum Thermal Process

    SciTech Connect (OSTI)

    Korinko, Paul S.; Tosten, Michael H.

    2013-01-01

    Radioactive contamination with a gamma energy emission consistent with {sup 65}Zn was detected in a glovebox following a vacuum thermal process. The contaminated components were removed from the glovebox and subjected to examination. Selected analytical techniques were used to determine the nature of the precursor material, i.e., oxide or metallic, the relative transferability of the deposit and its nature. The deposit was determined to be borne from natural zinc and was further determined to be deposited as a metallic material from vapor.

  12. Extracellular Proteins Promote Zinc Sulfide Aggregation

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

    Extracellular Proteins Promote Zinc Sulfide Aggregation Print Researchers from the ALS, Berkeley Lab's National Center for Electron Microscopy (NCEM), and Lawrence Livermore National Laboratory analyzed biofilm samples rich in zinc sulfide and dominated by sulfate-reducing bacteria, which were collected from lead-zinc mine waters. The researchers were curious about the relationship of the organic material and metals, particularly how organics affect mobility, and its potential for

  13. Extracellular Proteins Promote Zinc Sulfide Aggregation

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

    Extracellular Proteins Promote Zinc Sulfide Aggregation Print Researchers from the ALS, Berkeley Lab's National Center for Electron Microscopy (NCEM), and Lawrence Livermore National Laboratory analyzed biofilm samples rich in zinc sulfide and dominated by sulfate-reducing bacteria, which were collected from lead-zinc mine waters. The researchers were curious about the relationship of the organic material and metals, particularly how organics affect mobility, and its potential for

  14. Extracellular Proteins Promote Zinc Sulfide Aggregation

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

    Extracellular Proteins Promote Zinc Sulfide Aggregation Print Researchers from the ALS, Berkeley Lab's National Center for Electron Microscopy (NCEM), and Lawrence Livermore National Laboratory analyzed biofilm samples rich in zinc sulfide and dominated by sulfate-reducing bacteria, which were collected from lead-zinc mine waters. The researchers were curious about the relationship of the organic material and metals, particularly how organics affect mobility, and its potential for

  15. Extracellular Proteins Promote Zinc Sulfide Aggregation

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

    Extracellular Proteins Promote Zinc Sulfide Aggregation Print Researchers from the ALS, Berkeley Lab's National Center for Electron Microscopy (NCEM), and Lawrence Livermore National Laboratory analyzed biofilm samples rich in zinc sulfide and dominated by sulfate-reducing bacteria, which were collected from lead-zinc mine waters. The researchers were curious about the relationship of the organic material and metals, particularly how organics affect mobility, and its potential for

  16. Extracellular Proteins Promote Zinc Sulfide Aggregation

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

    Extracellular Proteins Promote Zinc Sulfide Aggregation Print Researchers from the ALS, Berkeley Lab's National Center for Electron Microscopy (NCEM), and Lawrence Livermore National Laboratory analyzed biofilm samples rich in zinc sulfide and dominated by sulfate-reducing bacteria, which were collected from lead-zinc mine waters. The researchers were curious about the relationship of the organic material and metals, particularly how organics affect mobility, and its potential for

  17. Extracellular Proteins Promote Zinc Sulfide Aggregation

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

    Extracellular Proteins Promote Zinc Sulfide Aggregation Print Researchers from the ALS, Berkeley Lab's National Center for Electron Microscopy (NCEM), and Lawrence Livermore National Laboratory analyzed biofilm samples rich in zinc sulfide and dominated by sulfate-reducing bacteria, which were collected from lead-zinc mine waters. The researchers were curious about the relationship of the organic material and metals, particularly how organics affect mobility, and its potential for

  18. Extracellular Proteins Promote Zinc Sulfide Aggregation

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

    can organize sulfide nanoparticles into semiconductor nanowires. The research team used a series of imaging techniques and detectors to analyze aggregates of biogenic zinc sulfide...

  19. Zinc Matrix Power Inc | Open Energy Information

    Open Energy Info (EERE)

    California Zip: 93101 Product: Develops high-performance rechargeable alkaline battery technology for commercial and military markets. References: Zinc Matrix Power Inc1...

  20. Tinkering with Zinc | The Ames Laboratory

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

    and lack the stability necessary to directly study their role in important catalytic industrial processes. Zinc is not a transition metal, but some of its properties are...

  1. Extracellular Proteins Promote Zinc Sulfide Aggregation

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

    Lab's National Center for Electron Microscopy (NCEM), and Lawrence Livermore National Laboratory analyzed biofilm samples rich in zinc sulfide and dominated by sulfate-reducing...

  2. Extracellular Proteins Promote Zinc Sulfide Aggregation

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

    for Electron Microscopy (NCEM), and Lawrence Livermore National Laboratory analyzed biofilm samples rich in zinc sulfide and dominated by sulfate-reducing bacteria, which were...

  3. Summary and assessment of METC zinc ferrite hot coal gas desulfurization test program, final report: Volume 1

    SciTech Connect (OSTI)

    Underkoffler, V.S.

    1986-12-01

    The Morgantown Energy Technology Center (METC) has conducted a test program to develop a zinc ferrite-based high temperature desulfurization process which could be applied to fuel gas entering downstream components such as molten carbonate fuel cells or gas turbines. As a result of prior METC work with iron oxide and zinc oxide sorbents, zinc ferrite evolved as a candidate with the potential for high capacity, low equilibrium levels of H/sub 2/S, and structural stability after multiple regenerations. The program consisted of laboratory-scale testing with a two-inch diameter reactor and simulated fixed-bed gasifier gas; bench-scale testing with a six-inch diameter reactor and actual gas from the METC 42-inch fixed bed gasifier; as well as laboratory-scale testing of zinc ferrite with simulated fluidized bed gasifier gas. Optimum operating parameters for zinc ferrite such as temperatures, gas compositions, and space velocities are discussed. From the test results, salient features of zinc ferrite were derived and discussed in regard to system implications, issues raised, and technical requirements. 47 refs., 53 figs., 41 tabs.

  4. Rechargeable zinc cell with alkaline electrolyte which inhibits shape change in zinc electrode

    DOE Patents [OSTI]

    Adler, Thomas C.; McLarnon, Frank R.; Cairns, Elton J.

    1994-01-01

    An improved rechargeable zinc cell is described comprising a zinc electrode and another electrode such as, for example, a nickel-containing electrode, and having an electrolyte containing KOH and a combination of KF and K.sub.2 CO.sub.3 salts which inhibits shape change in the zinc electrode, i.e., the zinc electrode exhibits low shape change, resulting in an improved capacity retention of the cell over an number of charge-discharge cycles, while still maintaining high discharge rate characteristics.

  5. Rechargeable zinc cell with alkaline electrolyte which inhibits shape change in zinc electrode

    DOE Patents [OSTI]

    Adler, T.C.; McLarnon, F.R.; Cairns, E.J.

    1994-04-12

    An improved rechargeable zinc cell is described comprising a zinc electrode and another electrode such as, for example, a nickel-containing electrode, and having an electrolyte containing KOH and a combination of KF and K[sub 2]CO[sub 3] salts which inhibits shape change in the zinc electrode, i.e., the zinc electrode exhibits low shape change, resulting in an improved capacity retention of the cell over an number of charge-discharge cycles, while still maintaining high discharge rate characteristics. 8 figures.

  6. Durable Zinc Oxide-Based Regenerable Sorbents for Desulfurization

    Office of Scientific and Technical Information (OSTI)

    0 F) and pressures of 203-2026 kPa(2 to 20 atm) with a feed containing 1.2 vol% H 2 S. The ... O 2) at temperatures as low as 370 0 C (700 0 F) and pressures of 304-709 kPa(3 to 7 atm). ...

  7. Effects of Humidity During Formation of Zinc Oxide Electron Contact...

    Office of Scientific and Technical Information (OSTI)

    Additional Journal Information: Journal Volume: 31; Related Information: Organic Electronics; Journal ID: ISSN 1566-1199 Publisher: Elsevier Research Org: NREL (National Renewable ...

  8. Nature of the green luminescent center in zinc oxide

    SciTech Connect (OSTI)

    Vanheusden, K.; Warren, W.L.; Seager, C.H.; Tallant, D.R.; Caruso, J.; Hampden-Smith, M.J.; Kodas, T.T.

    1996-12-31

    EPR, optical absorption, and photoluminescence spectroscopies are used to characterize a wide range of different ZnO phosphor powders. A good correlation is generally observed between the 510-nm green emission intensity and the density of paramagnetic isolated oxygen vacancies. Both quantities are found to peak at a free-carrier density of about 1.4x10{sup 18}cm{sup -3}. The green emission intensity can be strongly influenced by free-carrier depletion at the particle surface, especially for small particles and/or low doping. The data suggest that the green PL in ZnO phosphors is due to recombination of electrons in singly occupied oxygen vacancies with photoexcited holes in the valence band.

  9. Photovoltaic devices comprising zinc stannate buffer layer and method for making

    DOE Patents [OSTI]

    Wu, Xuanzhi; Sheldon, Peter; Coutts, Timothy J.

    2001-01-01

    A photovoltaic device has a buffer layer zinc stannate Zn.sub.2 SnO.sub.4 disposed between the semiconductor junction structure and the transparent conducting oxide (TCO) layer to prevent formation of localized junctions with the TCO through a thin window semiconductor layer, to prevent shunting through etched grain boundaries of semiconductors, and to relieve stresses and improve adhesion between these layers.

  10. Zinc subsea production system: An overview

    SciTech Connect (OSTI)

    Bednar, J.M. )

    1994-04-01

    Exxon Co. U.S.A.'s Zinc development, in 1,460 ft of water in the Gulf of Mexico, uses a subsea production system to produce gas to a host platform 6 miles away. The 10-slot subsea template, designed specifically to accommodate the soft soil conditions at the Zinc site, supports the non-through-flowline (non-TFL) wells, which are controlled by means of an electrohydraulic control system. This paper describes key features of the development.

  11. Hyper-dendritic nanoporous zinc foam anodes

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

    Chamoun, Mylad; Hertzberg, Benjamin J.; Gupta, Tanya; Davies, Daniel; Bhadra, Shoham; Van Tassell, Barry.; Erdonmez, Can; Steingart, Daniel A.

    2015-04-24

    The low cost, significant reducing potential, and relative safety of the zinc electrode is a common hope for a reductant in secondary batteries, but it is limited mainly to primary implementation due to shape change. In this work we exploit such shape change for the benefit of static electrodes through the electrodeposition of hyper-dendritic nanoporous zinc foam. Electrodeposition of zinc foam resulted in nanoparticles formed on secondary dendrites in a three-dimensional network with a particle size distribution of 54.1 - 96.0 nm. The nanoporous zinc foam contributed to highly oriented crystals, high surface area and more rapid kinetics in contrastmore » to conventional zinc in alkaline mediums. The anode material presented had a utilization of ~ 88% at full depth-of-discharge at various rates indicating a superb rate-capability. The rechargeability of Zn⁰/Zn²⁺ showed significant capacity retention over 100 cycles at a 40% depth-of-discharge to ensure that the dendritic core structure was imperforated. The dendritic architecture was densified upon charge-discharge cycling and presented superior performance compared to bulk zinc electrodes.« less

  12. Two-stage regeneration of zinc ferrite desulfurization sorbent

    SciTech Connect (OSTI)

    Jha, M.C.; Berggren, M.H.

    1988-06-28

    The Morgantown Energy Technology Center (METC) of the US Department of Energy (DOE) is interested in the potential of using a two-step process for regenerating the zinc ferrite desulfurization sorbent. In the first regeneration step, a gas mixture consisting of 12 percent SO{sub 2}, 2 percent O{sub 2}, and 86 percent N{sub 2} is used to convert zinc and iron sulfides to their sulfate forms using a sorbent bed inlet temperature of about 850{degrees}F (454{degrees}C). For the second step, the temperature is raised to about 1400{degrees}F (760{degrees}C), and the sulfates are decomposed to oxides with the concurrent release of sulfur dioxide. The same gas composition used for first step is also used for the second step. The proposed technique would require no steam and also has the advantage of producing a regeneration gas rich in sulfur dioxide. In a commercial operation, recirculating regeneration gas would be supplemented with air as required to supply the necessary oxygen. A bleed stream from regeneration (concentrated SO{sub 2} gas in nitrogen) would constitute feed to sulfur recovery.

  13. Zinc air refuelable battery: alternative zinc fuel morphologies and cell behavior

    SciTech Connect (OSTI)

    Cooper, J.F.; Krueger, R.

    1997-01-01

    Multicell zinc/air batteries have been tested previously in the laboratory and as part of the propulsion system of an electric bus; cut zinc wire was used as the anode material. This battery is refueled by a hydraulic transport of 0.5-1 mm zinc particles into hoppers above each cell. We report an investigation concerning alternative zinc fuel morphologies, and energy losses associated with refueling and with overnight or prolonged standby. Three types of fuel pellets were fabricated, tested and compared with results for cut wire: spheres produced in a fluidized bed electrolysis cell; elongated particles produced by gas-atomization; and pellets produced by chopping 1 mm porous plates made of compacted zinc fines. Relative sizes of the particles and cell gap dimensions are critical. All three types transported within the cell 1553 and showed acceptable discharge characteristics, but a fluidized bed approach appears especially attractive for owner/user recovery operations.

  14. Zinc halogen battery electrolyte composition with lead additive

    DOE Patents [OSTI]

    Henriksen, Gary L.

    1981-01-01

    This disclosure relates to a zinc halogen battery electrolyte composition containing an additive providing improved zinc-on-zinc recyclability. The improved electrolyte composition involves the use of a lead additive to inhibit undesirable irregular plating and reduce nodular or dendritic growth on the electrode surface. The lead-containing electrolyte composition of the present invention appears to influence not only the morphology of the base plate zinc, but also the morphology of the zinc-on-zinc replate. In addition, such lead-containing electrolyte compositions appear to reduce hydrogen formation.

  15. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Quarterly technical progress report 8, July--September 1988

    SciTech Connect (OSTI)

    Jha, M.C.; Berggren, M.H.

    1988-11-14

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  16. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Quarterly technical progress report 9, October--December 1988

    SciTech Connect (OSTI)

    Jha, M.C.; Berggren, M.H.

    1989-03-06

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  17. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Quarterly technical progress report No. 3, April--June 1987

    SciTech Connect (OSTI)

    Jha, M.C.; Baltich, L.K.; Berggren, M.H.

    1987-08-28

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  18. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Quarterly technical progress report 2, January--March 1987

    SciTech Connect (OSTI)

    Jha, M.C.; Baltich, L.K.; Berggren, M.H.

    1987-05-18

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  19. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Volume 1, Bench-scale testing and analysis

    SciTech Connect (OSTI)

    Jha, M.C.; Berggren, M.H.

    1989-05-02

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  20. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Quarterly technical progress report 7, April--June 1988

    SciTech Connect (OSTI)

    Jha, M.C.; Berggren, M.H.

    1988-08-19

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  1. Hydrometallurgical process for recovering iron sulfate and zinc sulfate from baghouse dust

    DOE Patents [OSTI]

    Zaromb, Solomon; Lawson, Daniel B.

    1994-01-01

    A process for recovering zinc/rich and iron-rich fractions from the baghouse dust that is generated in various metallurgical operations, especially in steel-making and other iron-making plants, comprises the steps of leaching the dust by hot concentrated sulfuric acid so as to generate dissolved zinc sulfate and a precipitate of iron sulfate, separating the precipitate from the acid by filtration and washing with a volatile liquid, such as methanol or acetone, and collecting the filtered acid and the washings into a filtrate fraction. The volatile liquid may be recovered distillation, and the zinc may be removed from the filtrate by alternative methods, one of which involves addition of a sufficient amount of water to precipitate hydrated zinc sulfate at 10.degree. C., separation of the precipitate from sulfuric acid by filtration, and evaporation of water to regenerate concentrated sulfuric acid. The recovery of iron may also be effected in alternative ways, one of which involves roasting the ferric sulfate to yield ferric oxide and sulfur trioxide, which can be reconverted to concentrated sulfuric acid by hydration. The overall process should not generate any significant waste stream.

  2. Hydrometallurgical process for recovering iron sulfate and zinc sulfate from baghouse dust

    DOE Patents [OSTI]

    Zaromb, S.; Lawson, D.B.

    1994-02-15

    A process for recovering zinc-rich and iron-rich fractions from the baghouse dust that is generated in various metallurgical operations, especially in steel-making and other iron-making plants, comprises the steps of leaching the dust by hot concentrated sulfuric acid so as to generate dissolved zinc sulfate and a precipitate of iron sulfate, separating the precipitate from the acid by filtration and washing with a volatile liquid, such as methanol or acetone, and collecting the filtered acid and the washings into a filtrate fraction. The volatile liquid may be recovered by distillation, and the zinc may be removed from the filtrate by alternative methods, one of which involves addition of a sufficient amount of water to precipitate hydrated zinc sulfate at 10 C, separation of the precipitate from sulfuric acid by filtration, and evaporation of water to regenerate concentrated sulfuric acid. The recovery of iron may also be effected in alternative ways, one of which involves roasting the ferric sulfate to yield ferric oxide and sulfur trioxide, which can be reconverted to concentrated sulfuric acid by hydration. The overall process should not generate any significant waste stream. 1 figure.

  3. Ion flotation of zinc using ethylhexadecyldimethylammonium bromide

    SciTech Connect (OSTI)

    McDonald, C.W.; Ogunkeye, O.A.

    1981-01-01

    Zinc ions react with the surfactant ethylhexadecyldimethylammonium bromide (EHDABr) to form a surface active sublate which can be removed from aqueous chloride solutions by ion flotation. A typical ion flotation procedure involves passing air through a 235-ml solution containing 5 ppM Zn/sup 2 +/, 2.0 M HCl, and 2.5 x 10/sup -3/ M EHDABr at a flow rate of 40 ml/min for 150 min. The procedure is simple and rapid. Cadmium, copper, lead, and nickel ions cause reductions of zinc flotation efficiencies of less than 2.5% under the experimental conditions. 5 tables.

  4. Rechargeable zinc cell with alkaline electrolyte which inhibits shape change in zinc electrode

    DOE Patents [OSTI]

    Adler, Thomas C.; McLarnon, Frank R.; Cairns, Elton J.

    1995-01-01

    An improved rechargeable zinc cell is described comprising a zinc electrode and another electrode such as, for example, a nickel-containing electrode, and having an electrolyte containing one or more hydroxides having the formula M(OH), one or more fluorides having the formula MF, and one or more carbonates having the formula M.sub.2 CO.sub.3, where M is a metal selected from the group consisting of alkali metals. The electrolyte inhibits shape change in the zinc electrode, i.e., the zinc electrode exhibits low shape change, resulting in an improved capacity retention of the cell over an number of charge-discharge cycles, while still maintaining high discharge rate characteristics.

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

    DOE Patents [OSTI]

    Coops, Melvin S.

    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.

  6. Zinc-bromine batteries with improved electrolyte

    SciTech Connect (OSTI)

    Kantner, E.

    1985-01-01

    The coulombic efficiency of aqueous zinc bromine batteries can be increased if, in addition to the bromide ions required to be present in the electrolyte to charge the cell to rated capacity, chloride ions are added to the electrolyte in amounts sufficient to reduce the amount of free bromine present in the electrolyte during operation of the cell.

  7. Zinc bromide battery development. Final report

    SciTech Connect (OSTI)

    Leo, A.

    1986-01-01

    Earlier EPRI work demonstrated the potential of zinc bromide batteries to provide long-life, low-cost energy storage for utilities. The latest developments, summarized in this report, include improvements in electrode, separator, and other components, as well as successful testing of cell stacks.

  8. Zinc Bromide Waste Solution Treatment Options

    SciTech Connect (OSTI)

    Langston, C.A.

    2001-01-16

    The objective of this effort was to identify treatment options for 20,000 gallons of low-level radioactively contaminated zinc bromide solution currently stored in C-Area. These options will be relevant when the solutions are declared waste.

  9. Porous desulfurization sorbent pellets containing a reactive metal oxide and an inert zirconium compound

    SciTech Connect (OSTI)

    Gardner, Todd H.; Gasper-Galvin, Lee D.

    1996-12-01

    Sorbent pellets for removing hydrogen sulfide from coal gas are prepared by combining a reactive oxide, in particular zinc oxide, with a zirconium compound such as an oxide, silicate, or aluminate of zirconium, and an inorganic binder and pelletizing and calcining the mixture. Alternately, the zinc oxide may be replaced by copper oxide or a combination of copper, molybdenum, and manganese oxides. The pellet components may be mixed in dry form, moistened to produce a paste, and converted to pellets by forming an aqueous slurry of the components and spray drying the slurry, or the reactive oxide may be formed on existing zirconium-containing catalyst-carrier pellets by infusing a solution of a salt of the active metal onto the existing pellets and firing at a high temperature to produce the oxide. Pellets made according to this invention show a high reactivity with hydrogen sulfide and durability such as to be useful over repeated cycles of sorption and regeneration.

  10. Preparation of ionic membranes for zinc/bromine storage batteries

    SciTech Connect (OSTI)

    Assink, R.A.; Arnold, C. Jr.

    1991-01-01

    Zinc/bromine flow batteries are being developed for vehicular and utility load leveling applications. During charge, an aqueous zinc bromide salt is electolyzed to zinc metal and molecular bromine. During discharge, the zinc and bromine react to again form the zinc bromide salt. One serious disadvantage of the microporous separators presently used in the zinc/bromine battery is that modest amounts of bromine and negatively charged bromine moieties permeate through these materials and react with the zinc anode. This results in partial self-discharge of the battery and low coulombic efficiencies. Our approach to this problem is to impregnate the microporous separators with a soluble cationic polyelectrolyte. In laboratory screening tests a sulfonated polysulfone resin and fully fluorinated sulfonic acid polymer substantially reduced bromine permeation with only modest increases in the area resistance. 5 refs., 6 figs., 11 tabs.

  11. Zinc deposition in acid lakes: the role of diffusion

    SciTech Connect (OSTI)

    Carignan, R.; Tessier, A.

    1985-06-28

    Steep negative concentration gradients of dissolved zinc are present between the overlying waters and the anoxic pore waters of two acid lakes. In the anoxic pore waters, the low zinc concentrations can be explained as due to the formation of relatively insoluble zinc sulfide minerals. Downward diffusive fluxes of dissolved zinc account for at least 50 to 75% of the recent zinc deposition to the sediments of these lakes. This downward diffusion occurs to a depth of 2 to 3 centimeters below the sediment water interface, where pronounced maxima in total zinc are observed. These subsurface peaks in total zinc have been interpreted as an indication of recent lake acidification. The present observations indicate that such subsurface peaks may also result from a diagenetic activity unrelated to recent changes in lake acidity. 22 references, 1 figure, 2 tables.

  12. Studies of the Atomic and Crystalline Characteristics of Ceramic Oxide Nano Powders after Bio field Treatment

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

    Article Open Access Industrial Engineering & Management Trivedi et al., Ind Eng Manage 2015, 4:3 http://dx.doi.org/10.4172/2169-0316.1000161 Volume 4 * Issue 3 * 1000161 Ind Eng Manage ISSN: 2169-0316, IEM an open access journal Keywords: Biofield treatment; Iron oxide; Copper oxide; Zinc oxide; X-ray diffraction; FT-IR Introduction Transition metal oxides (TMOs) exhibit fascinating properties such as piezoelectricity, ferroelectricity, nonlinear optical behaviour, wide band gap and high-TC

  13. Heat up and potential failure of BWR upper internals during a severe accident

    SciTech Connect (OSTI)

    Robb, Kevin R

    2015-01-01

    In boiling water reactors, the steam dome, steam separators, and dryers above the core are comprised of approximately 100 tons of stainless steel. During a severe accident in which the coolant boils away and exothermic oxidation of zirconium occurs, gases (steam and hydrogen) are superheated in the core region and pass through the upper internals. Historically, the upper internals have been modeled using severe accident codes with relatively simple approximations. The upper internals are typically modeled in MELCOR as two lumped volumes with simplified heat transfer characteristics, with no structural integrity considerations, and with limited ability to oxidize, melt, and relocate. The potential for and the subsequent impact of the upper internals to heat up, oxidize, fail, and relocate during a severe accident was investigated. A higher fidelity representation of the shroud dome, steam separators, and steam driers was developed in MELCOR v1.8.6 by extending the core region upwards. This modeling effort entailed adding 45 additional core cells and control volumes, 98 flow paths, and numerous control functions. The model accounts for the mechanical loading and structural integrity, oxidation, melting, flow area blockage, and relocation of the various components. The results indicate that the upper internals can reach high temperatures during a severe accident; they are predicted to reach a high enough temperature such that they lose their structural integrity and relocate. The additional 100 tons of stainless steel debris influences the subsequent in-vessel and ex-vessel accident progression.

  14. Solid oxide fuel cell with monolithic core

    DOE Patents [OSTI]

    McPheeters, C.C.; Mrazek, F.C.

    1988-08-02

    A solid oxide fuel cell in which fuel and oxidant gases undergo an electrochemical reaction to produce an electrical output includes a monolithic core comprised of a corrugated conductive sheet disposed between upper and lower generally flat sheets. The corrugated sheet includes a plurality of spaced, parallel, elongated slots which form a series of closed, linear, first upper and second lower gas flow channels with the upper and lower sheets within which a fuel gas and an oxidant gas respectively flow. Facing ends of the fuel cell are generally V-shaped and provide for fuel and oxidant gas inlet and outlet flow, respectively, and include inlet and outlet gas flow channels which are continuous with the aforementioned upper fuel gas and lower oxidant gas flow channels. The upper and lower flat sheets and the intermediate corrugated sheet are preferably comprised of ceramic materials and are securely coupled together such as by assembly in the green state and sintering together during firing at high temperatures. A potential difference across the fuel cell, or across a stacked array of similar fuel cells, is generated when an oxidant gas such as air and a fuel such as hydrogen gas is directed through the fuel cell at high temperatures, e.g., between 700 C and 1,100 C. 8 figs.

  15. Solid oxide fuel cell with monolithic core

    DOE Patents [OSTI]

    McPheeters, Charles C.; Mrazek, Franklin C.

    1988-01-01

    A solid oxide fuel cell in which fuel and oxidant gases undergo an electrochemical reaction to produce an electrical output includes a monolithic core comprised of a corrugated conductive sheet disposed between upper and lower generally flat sheets. The corrugated sheet includes a plurality of spaced, parallel, elongated slots which form a series of closed, linear, first upper and second lower gas flow channels with the upper and lower sheets within which a fuel gas and an oxidant gas respectively flow. Facing ends of the fuel cell are generally V-shaped and provide for fuel and oxidant gas inlet and outlet flow, respectively, and include inlet and outlet gas flow channels which are continuous with the aforementioned upper fuel gas and lower oxidant gas flow channels. The upper and lower flat sheets and the intermediate corrugated sheet are preferably comprised of ceramic materials and are securely coupled together such as by assembly in the green state and sintering together during firing at high temperatures. A potential difference across the fuel cell, or across a stacked array of similar fuel cells, is generated when an oxidant gas such as air and a fuel such as hydrogen gas is directed through the fuel cell at high temperatures, e.g., between 700.degree. C. and 1100.degree. C.

  16. Electrolyte for zinc bromine storage batteries

    SciTech Connect (OSTI)

    Ando, Y.; Ochiai, T.

    1985-04-09

    A negative electrolyte for electrolyte circulation-type storage batteries has a composition basically comprising zinc bromide as an active material and this active material is mixed with specified amounts of quaternary ammonium bromides of heterocyclic compounds such as morpholine, pyridine and pyrrolidine or ammonia as a bromine complexing agent and a dendrite inhibitor with or without specified amounts of Sn/sup 2 +/ and Pb/sup 2 +/.

  17. Chemical enhancement of metallized zinc anode performance

    SciTech Connect (OSTI)

    Bennett, J.

    1998-12-31

    Galvanic current delivered to reinforced concrete by a metallized zinc anode was studied relative to the humidity of its environment and periodic direct wetting. Current decreased quickly at low humidity to values unlikely to meet accepted cathodic protection criteria, but could be easily restored by direct wetting of the anode. Thirteen chemicals were screened for their ability to enhance galvanic current. Such chemicals, when applied to the exterior surface of the anode, are easily transported by capillary action to the anode-concrete interface where they serve to maintain the interface conductive and the zinc electrochemically active. The most effective chemicals were potassium and lithium bromide, acetate, chloride and nitrate, which increased galvanic current by a factor of 2--15, depending on relative humidity and chloride contamination of the concrete. This new technique is expected to greatly expand the number of concrete structures which can be protected by simple galvanic cathodic protection, The use of lithium-based chemicals together with metallized zinc anode is also proposed for mitigation of existing problems due to ASR. In this case, lithium which prevents or inhibits expansion due to ASR can be readily injected into the concrete. A new process, electrochemical maintenance of concrete (EMC), is also proposed to benefit reinforced concrete structures suffering from chloride-induced corrosion.

  18. Occupational hypersensitivity pneumonitis in a smelter exposed to zinc fumes

    SciTech Connect (OSTI)

    Ameille, J.; Brechot, J.M.; Brochard, P.; Capron, F.; Dore, M.F. )

    1992-03-01

    A smelter exposed to zinc fumes reported severe recurrent episodes of cough, dyspnea and fever. Bronchoalveolar lavage showed a marked increase in lymphocytes count with predominance of CD8 T-lymphocytes. Presence of zinc in alveolar macrophages was assessed by analytic transmission electron microscopy. This is the first case of recurrent bronchoalveolitis related to zinc exposure in which the clinical picture and BAL results indicate a probable hypersensitivity pneumonitis.

  19. Excitation Energies of Zinc Porphyrin in Aqueous Solution Using...

    Office of Scientific and Technical Information (OSTI)

    Theory Citation Details In-Document Search Title: Excitation Energies of Zinc Porphyrin in Aqueous Solution Using Long-Range Corrected Time-Dependent Density Functional Theory ...

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

    DOE Patents [OSTI]

    Poston, James A.

    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.

  1. 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.

  2. Novel solar light driven photocatalyst, zinc indium vanadate for photodegradation of aqueous phenol

    SciTech Connect (OSTI)

    Mahapure, Sonali A.; Ambekar, Jalindar D.; Nikam, Latesh K.; Marimuthu, R.; Kulkarni, Milind V.

    2011-05-15

    Graphical abstract: Novel photocatalyst, zinc indium vanadate (ZnIn{sub 2}V{sub 2}O{sub 9}) demonstrated and showed an excellent photocatalytic activity for phenol degradation under visible light. Research highlights: {yields} Designing and identification of a photocatalyst having prospective potential application to be used in visible light (400-800 nm). {yields} Successful synthesis of novel ZnIn{sub 2}V{sub 2}O{sub 9} by solid state route. {yields} Confirmation of the designed product using characterization techniques. {yields} Application study comprising photodegradation of aqueous phenol at visible light despite of UV radiations. -- Abstract: In the present investigation, we have demonstrated the synthesis of novel photocatalyst, zinc indium vanadate (ZIV) by solid-solid state route using respective oxides of zinc, indium and vanadium. This novel photocatalyst was characterized using XRD, FESEM, UV-DRS and FTIR in order to investigate its structural, morphological and optical properties. XRD clearly shows the formation of phase pure ZIV of triclinic crystal structure with good crystallinity. FESEM micrographs showed the clustered morphology having particle size between 0.5 and 1 {mu}m. Since, optical study showed the band gap around 2.8 eV, i.e. in visible region, we have performed the photocatalytic activity of phenol degradation under visible light irradiation. The photodecomposition of phenol by ZIV is studied for the first time and an excellent photocatalytic activity was obtained using this novel photocatalyst. Considering the band gap of zinc indium vanadate in visible region, it will also be the potential candidate for water splitting.

  3. Zinc electrode morphology in acid electrolytes. Annual report, March 15, 1982-March 15, 1983

    SciTech Connect (OSTI)

    McBreen, J.; Gannon, E.

    1983-07-01

    The zinc electrode is common to both zinc/chlorine and zinc/bromine flow batteries. Although considerable progress has been made in engineering these batteries, there are still problems with the zinc electrode. The objective of this work is to elucidate the mechanism of zinc deposition in acid electrolytes and to devise methods to control zinc electrode morphology. In this subcontract, work focused on obtaining baseline data in ultra pure zinc chloride and zinc bromide electrolytes. Emphasis was on the initial stages of electrocrystallization. In addition, the effect of modified charging methods, organic surfactants, inorganic additives and substrates was investigated.

  4. Method of removing oxides of sulfur and oxides of nitrogen from exhaust gases

    DOE Patents [OSTI]

    Walker, Richard J.

    1986-01-01

    A continuous method is presented for removing both oxides of sulfur and oxides of nitrogen from combustion or exhaust gases with the regeneration of the absorbent. Exhaust gas is cleaned of particulates and HCl by a water scrub prior to contact with a liquid absorbent that includes an aqueous solution of bisulfite and sulfite ions along with a metal chelate, such as, an iron or zinc aminopolycarboxylic acid. Following contact with the combustion gases the spent absorbent is subjected to electrodialysis to transfer bisulfite ions into a sulfuric acid solution while splitting water with hydroxide and hydrogen ion migration to equalize electrical charge. The electrodialysis stack includes alternate layers of anion selective and bipolar membranes. Oxides of nitrogen are removed from the liquid absorbent by air stripping at an elevated temperature and the regenerated liquid absorbent is returned to contact with exhaust gases for removal of sulfur oxides and nitrogen oxides.

  5. Zinc surface complexes on birnessite: A density functional theory study

    SciTech Connect (OSTI)

    Kwon, Kideok D.; Refson, Keith; Sposito, Garrison

    2009-01-05

    Biogeochemical cycling of zinc is strongly influenced by sorption on birnessite minerals (layer-type MnO2), which are found in diverse terrestrial and aquatic environments. Zinc has been observed to form both tetrahedral (Zn{sup IV}) and octahedral (Zn{sup VI}) triple-corner-sharing surface complexes (TCS) at Mn(IV) vacancy sites in hexagonal birnessite. The octahedral complex is expected to be similar to that of Zn in the Mn oxide mineral, chalcophanite (ZnMn{sub 3}O{sub 7} {center_dot} 3H{sub 2}O), but the reason for the occurrence of the four-coordinate Zn surface species remains unclear. We address this issue computationally using spin-polarized Density Functional Theory (DFT) to examine the Zn{sub IV}-TCS and Zn{sup VI}-TCS species. Structural parameters obtained by DFT geometry optimization were in excellent agreement with available experimental data on Zn-birnessites. Total energy, magnetic moments, and electron-overlap populations obtained by DFT for isolated Zn{sup IV}-TCS revealed that this species is stable in birnessite without a need for Mn(III) substitution in the octahedral sheet and that it is more effective in reducing undersaturation of surface O at a Mn vacancy than is Zn{sub VI}-TCS. Comparison between geometry-optimized ZnMn{sub 3}O{sub 7} {center_dot} 3H{sub 2}O (chalcophanite) and the hypothetical monohydrate mineral, ZnMn{sub 3}O{sub 7} {center_dot} H{sub 2}O, which contains only tetrahedral Zn, showed that the hydration state of Zn significantly affects birnessite structural stability. Finally, our study also revealed that, relative to their positions in an ideal vacancy-free MnO{sub 2}, Mn nearest to Zn in a TCS surface complex move toward the vacancy by 0.08-0.11 {angstrom}, while surface O bordering the vacancy move away from it by 0.16-0.21 {angstrom}, in agreement with recent X-ray absorption spectroscopic analyses.

  6. EFFECTIVENESS OF COPPER AND BRONZE FOR ZINC CAPTURE

    SciTech Connect (OSTI)

    Korinko, P. S.

    2012-11-02

    A series of experiments was conducted to determine the efficacy of using copper and bronze sheet and screen under high vacuum conditions to capture zinc vapor. The experiments were conducted in a parametric manner using a fixed zinc vaporization temperature (350°C) but varying the filter temperature from ambient to 550°C. Consistent with previous work, metallic zinc was deposited at low temperatures, but the deposit was non‐adherent. At an intermediate temperature range (350‐450°C), the deposit formed an alloy with both copper and bronze materials. At higher temperatures (> 500°C) the zinc did not deposit on the surfaces likely due to its high vapor pressure. Additional testing to optimize the zinc 'getter' chemistry and surface condition is warranted.

  7. Electrochemical Aging of Thermal-Sprayed Zinc Anodes on Concrete

    SciTech Connect (OSTI)

    Holcomb, G.R.; Bullard, S.J.; Covino, B.S. Jr.; Cramer, S.D.; Cryer, C.B.; McGill, G.E.

    1996-10-01

    Thermal-sprayed zinc anodes are used in impressed current cathodic protection systems for some of Oregon's coastal reinforced concrete bridges. Electrochemical aging of zinc anodes results in physical and chemical changes at the zinc-concrete interface. Concrete surfaces heated prior to thermal-spraying had initial adhesion strengths 80 pct higher than unheated surfaces. For electrochemical aging greater than 200 kC/m{sup 2} (5.2 A h/ft{sup 2}), there was no difference in adhesion strengths for zinc on preheated and unheated concrete. Adhesion strengths decreased monotonically after about 400 to 600 kC/m{sup 2} (10.4 to 15.6 A-h/ft{sup 2}) as a result of the reaction zones at the zinc-concrete interface. A zone adjacent to the metallic zinc (and originally part of the zinc coating) was primarily zincite (ZnO), with minor constituents of wulfingite (Zn(OH){sub 2}), simonkolleite (Zn{sub 5}(OH) {sub 8}C{sub l2}{sup .}H{sub 2}O), and hydrated zinc hydroxide sulfates (Zn{sub 4}SO{sub 4}(OH){sub 6}{sup .}xH{sub 2}O). This zone is the locus for cohesive fracture when the zinc coating separates from the concrete during adhesion tests. Zinc ions substitute for calcium in the cement paste adjacent to the coating as the result of secondary mineralization. The initial estimate of the coating service life based on adhesion strength measurements in accelerated impressed current cathodic protection tests is about 27 years.

  8. Enhanced durability for high-temperature desulfurization sorbents for moving-bed applications -- Option 3 program: Development and testing of additional zinc titanate sorbents. Final report, September 1992--May 1996

    SciTech Connect (OSTI)

    Ayala, R.E.; Chuck, T.L.

    1996-12-31

    GE is developing a moving-bed, high-temperature desulfurization system for the integrated gasification combined-cycle (IGCC) power cycle in which zinc-based regenerable sorbents are currently being used as desulfurization sorbents. Zinc titanate and other zinc-based oxides are being considered as sorbents for use in the Clean Coal Technology Demonstration Program at Tampa Electric Co.`s Polk Power Station. A key to success in the development of high-temperature desulfurization systems is the matching of sorbent properties for the selected process operating conditions, namely, sustainable desulfurization kinetics, high sulfur capacity, and mechanical durability over multiple cycles. Additionally, the sulfur species produced during regeneration of the sorbent must be in a form compatible with sulfur recovery systems, such as sulfuric acid or elemental sulfur processes. The objective of this contract is to identify and test sorbent fabrication methods and chemical compositions that enhance the long-term chemical reactivity and mechanical strength of zinc titanate and other novel sorbents for moving-bed, high-temperature desulfurization of coal-derived gases. A parametric study on the use of calcium sulfate additives to zinc titanate was conducted for zinc titanates having a 2:1 and 1.5:1 zinc-to-titanium molar ratio, and they showed a beneficial effect on crush strength of fresh 2:1 zinc titanate sorbents. In addition, a test procedure was developed to screen sorbent formulations based on resistance to spalling and pellet breakage induced by zinc sulfate formation in the presence of sulfur dioxide and excess oxygen conditions.

  9. Zinc-bromine battery development, Sandia Contract 48-8838

    SciTech Connect (OSTI)

    Richards, L.; Vanschalwijk, W.; Albert, G.; Tarjanyi, M.; Leo, A. ); Lott, S. )

    1990-05-01

    This report describes development activities on the zinc-bromine battery system conducted by Energy Research Corporation (ERC). The project was a cost-shared program supported by the US Department of Energy and managed through Sandia. The project began in September 1985 and ran through January 1990. The zinc-bromine battery has been identified as a promising alternative to conventional energy storage options for many applications. The low cost of the battery reactants and the potential for long life make the system an attractive candidate for bulk energy storage applications, such as utility load leveling. The battery stores energy by the electrolysis of an aqueous zinc bromide salt to zinc metal and dissolved bromine. Zinc is plated as a layer on the electrode surface while bromine is dissolved in the electrolyte and carried out of the stack. The bromine is then extracted from the electrolyte with an organic complexing agent in the positive electrolyte storage tank. On discharge the zinc and bromine are consumed, regenerating the zinc bromide salt. 5 refs., 44 figs.

  10. Electrochemical synthesis and characterization of zinc oxalate nanoparticles

    SciTech Connect (OSTI)

    Shamsipur, Mojtaba; Roushani, Mahmoud; Pourmortazavi, Seied Mahdi

    2013-03-15

    Highlights: ? Synthesis of zinc oxalate nanoparticles via electrolysis of a zinc plate anode in sodium oxalate solutions. ? Design of a Taguchi orthogonal array to identify the optimal experimental conditions. ? Controlling the size and shape of particles via applied voltage and oxalate concentration. ? Characterization of zinc oxalate nanoparticles by SEM, UVvis, FT-IR and TGDTA. - Abstract: A rapid, clean and simple electrodeposition method was designed for the synthesis of zinc oxalate nanoparticles. Zinc oxalate nanoparticles in different size and shapes were electrodeposited by electrolysis of a zinc plate anode in sodium oxalate aqueous solutions. It was found that the size and shape of the product could be tuned by electrolysis voltage, oxalate ion concentration, and stirring rate of electrolyte solution. A Taguchi orthogonal array design was designed to identify the optimal experimental conditions. The morphological characterization of the product was carried out by scanning electron microscopy. UVvis and FT-IR spectroscopies were also used to characterize the electrodeposited nanoparticles. The TGDTA studies of the nanoparticles indicated that the main thermal degradation occurs in two steps over a temperature range of 350430 C. In contrast to the existing methods, the present study describes a process which can be easily scaled up for the production of nano-sized zinc oxalate powder.

  11. Cadmium zinc sulfide by solution growth

    DOE Patents [OSTI]

    Chen, Wen S.

    1992-05-12

    A process for depositing thin layers of a II-VI compound cadmium zinc sulfide (CdZnS) by an aqueous solution growth technique with quality suitable for high efficiency photovoltaic or other devices which can benefit from the band edge shift resulting from the inclusion of Zn in the sulfide. A first solution comprising CdCl.sub.2 2.5H.sub.2 O, NH.sub.4 Cl, NH.sub.4 OH and ZnCl.sub.2, and a second solution comprising thiourea ((NH.sub.2).sub.2 CS) are combined and placed in a deposition cell, along with a substrate to form a thin i.e. 10 nm film of CdZnS on the substrate. This process can be sequentially repeated with to achieve deposition of independent multiple layers having different Zn concentrations.

  12. 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

  13. ON COMPUTING UPPER LIMITS TO SOURCE INTENSITIES

    SciTech Connect (OSTI)

    Kashyap, Vinay L.; Siemiginowska, Aneta [Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States); Van Dyk, David A.; Xu Jin [Department of Statistics, University of California, Irvine, CA 92697-1250 (United States); Connors, Alanna [Eureka Scientific, 2452 Delmer Street, Suite 100, Oakland, CA 94602-3017 (United States); Freeman, Peter E. [Department of Statistics, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213 (United States); Zezas, Andreas, E-mail: vkashyap@cfa.harvard.ed, E-mail: asiemiginowska@cfa.harvard.ed, E-mail: dvd@ics.uci.ed, E-mail: jinx@ics.uci.ed, E-mail: aconnors@eurekabayes.co, E-mail: pfreeman@cmu.ed, E-mail: azezas@cfa.harvard.ed [Physics Department, University of Crete, P.O. Box 2208, GR-710 03, Heraklion, Crete (Greece)

    2010-08-10

    A common problem in astrophysics is determining how bright a source could be and still not be detected in an observation. Despite the simplicity with which the problem can be stated, the solution involves complicated statistical issues that require careful analysis. In contrast to the more familiar confidence bound, this concept has never been formally analyzed, leading to a great variety of often ad hoc solutions. Here we formulate and describe the problem in a self-consistent manner. Detection significance is usually defined by the acceptable proportion of false positives (background fluctuations that are claimed as detections, or Type I error), and we invoke the complementary concept of false negatives (real sources that go undetected, or Type II error), based on the statistical power of a test, to compute an upper limit to the detectable source intensity. To determine the minimum intensity that a source must have for it to be detected, we first define a detection threshold and then compute the probabilities of detecting sources of various intensities at the given threshold. The intensity that corresponds to the specified Type II error probability defines that minimum intensity and is identified as the upper limit. Thus, an upper limit is a characteristic of the detection procedure rather than the strength of any particular source. It should not be confused with confidence intervals or other estimates of source intensity. This is particularly important given the large number of catalogs that are being generated from increasingly sensitive surveys. We discuss, with examples, the differences between these upper limits and confidence bounds. Both measures are useful quantities that should be reported in order to extract the most science from catalogs, though they answer different statistical questions: an upper bound describes an inference range on the source intensity, while an upper limit calibrates the detection process. We provide a recipe for computing upper

  14. Upper Division Hot Spring Geothermal Area | Open Energy Information

    Open Energy Info (EERE)

    Upper Division Hot Spring Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Upper Division Hot Spring Geothermal Area Contents 1 Area Overview 2 History...

  15. Chemical characterization of sediments and pore water from the upper Clark Fork River and Milltown Reservoir, Montana

    SciTech Connect (OSTI)

    Brumbaugh, W.G.; Ingersoll, C.G.; Kemble, N.E.; May, T.W.; Zajicek, J.L. . Midwest Science Center)

    1994-12-01

    The upper Clark Fork River basin in western Montana is widely contaminated by metals from past mining, milling, and smelting activities. As part of a comprehensive ecological risk assessment for the upper Clark Fork River, the authors measured physical and chemical characteristics of surficial sediment samples that were collected from depositional zones for subsequent toxicity evaluations. Sampling stations included five locations along the upper 200 km of the river, six locations in or near Milltown Reservoir and two tributary references. Concentrations of As, Cd, Cu, Mn, Pb, and Zn decreased from the upper stations to the downstream stations in the Clark Fork River but then increased in all Milltown Reservoir stations to levels similar to uppermost river stations. Large percentages of the total Cd, Cu, Pb, and Zn were extractable by dilute HCL for all samples. Copper and zinc accounted for greater than 95% of extractable metals on a molar basis. Acid-volatile sulfide (AVS) concentrations were typically moderate in grab sediment samples and appeared to regulate dissolved concentrations of Cd, Cu, and Zn in sediment pore waters. Acid-volatile sulfide is important in controlling metal solubility in the depositional areas of the Clark Fork River and should be monitored in any future studies. Spatial variability within a sampling station was high for Cu, Zn, and AVS; therefore, the potential for toxicity to sediment-dwelling organisms may be highly localized.

  16. 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.

  17. Solder for oxide layer-building metals and alloys

    DOE Patents [OSTI]

    Kronberg, James W.

    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.

  18. Coupling of oxidative dehydrogenation and aromatization reactions of butane

    SciTech Connect (OSTI)

    Xu, Wen-Qing; Suib, S.L. )

    1994-01-01

    Coupling of oxidative dehydrogenation and aromatization of butane by using a dual function catalyst has led to a significant enhancement of the yields (from 25 to 40%) and selectivities to aromatics (from 39 to 64%). Butane is converted to aromatics by using either zinc-promoted [Ga]-ZSM-5 or zinc and gallium copromoted [Fe]-ZSM-5 zeolite as a catalyst. However, the formation of aromatics is severely limited by hydrocracking of butane to methane, ethane, and propane due to the hydrogen formed during aromatization reactions. On the other hand, the oxidative dehydrogenation of butane to butene over molybdate catalysts is found to be accompanied by a concurrent undesirable reaction, i.e., total oxidation. When two of these reactions (oxidative dehydrogenation and aromatization of butane) are coupled by using a dual function catalyst they have shown to complement each other. It is believed that the rate-limiting step for aromatization (butane to butene) is increased by adding an oxidative dehydrogenation catalyst (Ga-Zn-Mg-Mo-O). The formation of methane, ethane, and propane was suppressed due to the removal of hydrogen initially formed as water. Studies of ammonia TPD show that the acidities of [Fe]-ZSM-5 are greatly affected by the existence of metal oxides such as Ga[sub 2]O[sub 3], MgO, ZnO, and MoO[sub 3]. 40 refs., 9 figs., 1 tab.

  19. Zinc Bromide Combustion: Implications for the Consolidated Incinerator Facility

    SciTech Connect (OSTI)

    Oji, L.N.

    1998-12-16

    In the nuclear industry, zinc bromide (ZnBr2) is used for radiation shielding. At Savannah River Site (SRS) zinc bromide solution, in appropriate configurations and housings, was used mainly for shielding in viewing windows in nuclear reactor and separation areas. Waste stream feeds that will be incinerated at the CIF will occasionally include zinc bromide solution/gel matrices.The CIF air pollution systems control uses a water-quench and steam atomizer scrubber that collects salts, ash and trace metals in the liquid phase. Water is re-circulated in the quench unit until a predetermined amount of suspended solids or dissolved salts are present. After reaching the threshold limit, "dirty liquid", also called "blowdown", is pumped to a storage tank in preparation for treatment and disposal. The air pollution control system is coupled to a HEPA pre-filter/filter unit, which removes particulate matter from the flue gas stream (1).The objective of this report is to review existing literature data on the stability of zinc bromide (ZnBr2) at CIF operating temperatures (>870 degrees C (1600 degrees F) and determine what the combustion products are in the presence of excess air. The partitioning of the combustion products among the quencher/scrubber solution, bottom ash and stack will also be evaluated. In this report, side reactions between zinc bromide and its combustion products with fuel oil were not taken into consideration.

  20. Embrittlement of stainless steel welds by contamination with zinc-rich paint

    SciTech Connect (OSTI)

    Johnson, J.M.; Gutzeit, J.

    1985-01-01

    Contamination of Type 321 stainless steel heater tubes with zinc-rich paint can lead to failures by zinc embrittlement. Following a review of the mechanism of zinc embrittlement, the failure mode is discussed in some detail. Results of laboratory tests are presented, which confirm field observations. Finally a proper cleaning procedure is recommended to alleviate the problem.

  1. Secondary battery containing zinc electrode with modified separator and method

    DOE Patents [OSTI]

    Poa, D.S.

    1984-02-16

    A battery containing a zinc electrode with a porous separator between the anode and cathode. The separator is a microporous substrate carrying therewith an organic solvent of benzene, toluene or xylene with a tertiary organic amine therein, wherein the tertiary amine has three carbon chains each containing from six to eight carbon atoms. The separator reduces the rate of zinc dentrite growth in the separator during battery operation prolonging battery life by preventing short circuits. A method of making the separator is also disclosed.

  2. Secondary battery containing zinc electrode with modified separator and method

    DOE Patents [OSTI]

    Poa, David S.; Yao, Neng-Ping

    1985-01-01

    A battery containing a zinc electrode with a porous separator between the anode and cathode. The separator is a microporous substrate carrying therewith an organic solvent of benzene, toluene or xylene with a tertiary organic amine therein, wherein the tertiary amine has three carbon chains each containing from six to eight carbon atoms. The separator reduces the rate of zinc dentrite growth in the separator during battery operation prolonging battery life by preventing short circuits. A method of making the separator is also disclosed.

  3. Thin film cadmium telluride, zinc telluride, and mercury zinc telluride solar cells

    SciTech Connect (OSTI)

    Chu, T.L. )

    1992-04-01

    This report describes research to demonstrate (1) thin film cadmium telluride solar cells with a quantum efficiency of 75% or higher at 0. 44 {mu}m and a photovoltaic efficiency of 11.5% or greater, and (2) thin film zinc telluride and mercury zinc telluride solar cells with a transparency to sub-band-gap radiation of 65% and a photovoltaic conversion efficiency of 5% and 8%, respectively. Work was directed at (1) depositing transparent conducting semiconductor films by solution growth and metal-organic chemical vapor deposition (MOCVD) technique, (2) depositing CdTe films by close-spaced sublimation (CSS) and MOCVD techniques, (3) preparing and evaluating thin film CdTe solar cells, and (4) preparing and characterizing thin film ZnTe, CD{sub 1-x}Zn{sub 1-x}Te, and Hg{sub 1-x}Zn{sub x}Te solar cells. The deposition of CdS films from aqueous solutions was investigated in detail, and their crystallographic, optical, and electrical properties were characterized. CdTe films were deposited from DMCd and DIPTe at 400{degrees}C using TEGa and AsH{sub 3} as dopants. CdTe films deposited by CSS had significantly better microstructures than those deposited by MOCVD. Deep energy states in CdTe films deposited by CSS and MOCVD were investigated. Thin films of ZnTe, Cd{sub 1- x}Zn{sub x}Te, and Hg{sub 1-x}Zn{sub x}Te were deposited by MOCVD, and their crystallographic, optical, and electrical properties were characterized. 67 refs.

  4. Upper Rio Grande Simulation Model (URGSIM)

    Energy Science and Technology Software Center (OSTI)

    2010-08-05

    URGSIM estimates the location of surface water and groundwater resources in the upper Rio Grande Basin between the Colorado-New Mexico state line, and Caballo Reservoir from 1975 - 2045. It is a mass balance hydrology model of the Upper Rio Grande surface water, groundwater, and water demand systems which runs at a monthly timestep from 1975-1999 in calibration mode, 2000 – 2004 in validation mode, and 2005 – 2045 in scenario analysis mode.

  5. Upper Skagit Indian Tribe - Strategic Energy Planning

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

    Upper Skagit Indian Tribe Tribal Lands Location Tribal lands Tribal lands Two Tribe Land sites: Two Tribe Land sites: Bow Hill Complex Bow Hill Complex The Tribal economic center with both development The Tribal economic center with both development & undeveloped lands. & undeveloped lands. Helmick Road Reservation Helmick Road Reservation The community & government center with both The community & government center with both developed & newly required community lands.

  6. Oxidation catalyst

    DOE Patents [OSTI]

    Ceyer, Sylvia T.; Lahr, David L.

    2010-11-09

    The present invention generally relates to catalyst systems and methods for oxidation of carbon monoxide. The invention involves catalyst compositions which may be advantageously altered by, for example, modification of the catalyst surface to enhance catalyst performance. Catalyst systems of the present invention may be capable of performing the oxidation of carbon monoxide at relatively lower temperatures (e.g., 200 K and below) and at relatively higher reaction rates than known catalysts. Additionally, catalyst systems disclosed herein may be substantially lower in cost than current commercial catalysts. Such catalyst systems may be useful in, for example, catalytic converters, fuel cells, sensors, and the like.

  7. Effect of cadmium, mercury, and zinc on the hepatic microsomal enzymes of Channa punctatus

    SciTech Connect (OSTI)

    Dalal, R.; Bhattacharya, S. )

    1994-06-01

    The increased use of heavy metals like cadmium and mercury in industry and agriculture, and their subsequent intrusion in indeterminate amounts into the environment has caused ecological and biological changes. In vivid contrast, zinc, one of the essential elements, and used in the cosmetic industry, is known to play a pivotal roles in various cellular processes. The seriousness and longevity of these metals in the environment are compounded by the fact that they are non-degradable with significant oxidizing capacity and substantial affinity for electronegative nucleophilic species in proteins and enzymes. Exposure of aquatic animals, especially fish, to these toxic metals for a prolonged period produces an intrinsic toxicity in relation to susceptible organs and/or tissues, although no serious morphological or anatomical changes in the animal or even their feeding behavior may occur. The p-hydroxylation of aniline by aniline hydroxylase (AH) and the N-demethylation of amines to generate formaldehyde (HCHO) by aminopyrine demethylase (APD) are the two oxygen-dependent reactions of microsomal mixed-function oxidase (MFOs) which control the pharmacological and toxicological activities of xenobiotics in mammalian and other species. While both these classical enzymes in fish are reported to demonstrate relatively low specific activity, they are used as criteria for delineating polluted areas. Unlike mammalian species, however, intoxication and interference of MFO enzymes by metal toxicants, especially during prolonged exposure, has not been investigated. The present report describes the results of studies from the concurrent exposure for 28 d to cadmium (CdCl[sub 2]), mercury (HgCl[sub 2]) or zinc (ZnCl[sub 2]) individually, on the AH and APD activities and microsomal protein content in liver of freshwater teleost Channa punctatus.

  8. Upper Cumberland E M C | Open Energy Information

    Open Energy Info (EERE)

    Upper Cumberland E M C Jump to: navigation, search Name: Upper Cumberland E M C Place: Tennessee Phone Number: 931-528-5449 or 931-372-2323 or 931-268-2123 or 931-268-5866 or...

  9. Upper Bound on the First Star Formation History (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    Upper Bound on the First Star Formation History Citation Details In-Document Search Title: Upper Bound on the First Star Formation History You are accessing a document from the ...

  10. Upper internals arrangement for a pressurized water reactor

    DOE Patents [OSTI]

    Singleton, Norman R; Altman, David A; Yu, Ching; Rex, James A; Forsyth, David R

    2013-07-09

    In a pressurized water reactor with all of the in-core instrumentation gaining access to the core through the reactor head, each fuel assembly in which the instrumentation is introduced is aligned with an upper internals instrumentation guide-way. In the elevations above the upper internals upper support assembly, the instrumentation is protected and aligned by upper mounted instrumentation columns that are part of the instrumentation guide-way and extend from the upper support assembly towards the reactor head in hue with a corresponding head penetration. The upper mounted instrumentation columns are supported laterally at one end by an upper guide tube and at the other end by the upper support plate.

  11. Transient fluctuations of intracellular zinc ions in cell proliferation

    SciTech Connect (OSTI)

    Li, Yuan; Maret, Wolfgang; Department of Anesthesiology, The University of Texas Medical Branch, Galveston, TX 77555

    2009-08-15

    Zinc is essential for cell proliferation, differentiation, and viability. When zinc becomes limited for cultured cells, DNA synthesis ceases and the cell cycle is arrested. The molecular mechanisms of actions of zinc are believed to involve changes in the availability of zinc(II) ions (Zn{sup 2+}). By employing a fluorescent Zn{sup 2+} probe, FluoZin-3 acetoxymethyl ester, intracellular Zn{sup 2+} concentrations were measured in undifferentiated and in nerve growth factor (NGF)-differentiated rat pheochromocytoma (PC12) cells. Intracellular Zn{sup 2+} concentrations are pico- to nanomolar in PC12 cells and are higher in the differentiated than in the undifferentiated cells. When following cellular Zn{sup 2+} concentrations for 48 h after the removal of serum, a condition that is known to cause cell cycle arrest, Zn{sup 2+} concentrations decrease after 30 min but, remarkably, increase after 1 h, and then decrease again to about one half of the initial concentration. Cell proliferation, measured by an MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay, decreases after both serum starvation and zinc chelation. Two peaks of Zn{sup 2+} concentrations occur within one cell cycle: one early in the G1 phase and the other in the late G1/S phase. Thus, fluctuations of intracellular Zn{sup 2+} concentrations and established modulation of phosphorylation signaling, via an inhibition of protein tyrosine phosphatases at commensurately low Zn{sup 2+} concentrations, suggest a role for Zn{sup 2+} in the control of the cell cycle. Interventions targeted at these picomolar Zn{sup 2+} fluctuations may be a way of controlling cell growth in hyperplasia, neoplasia, and diseases associated with aberrant differentiation.

  12. Upper Skagit Indian Tribe- 2005 Project

    Broader source: Energy.gov [DOE]

    The Upper Skagit Indian Tribe lands consist of 550 acres of the Bow Hill Complex with reservation and new development economic lands located in Skagit County, Washington, adjacent to Interstate 5. The strategic energy plan would complete an assessment of the existing economic enterprises including hotel, convention center, and casino, plus potential green energy sources to serve the existing and developing facilities. The strategic energy analysis would complete an assessment of 50 acres acquired in October 2004, to build more low-income houses, and identify energy improvements for the existing fully developed 74 acres of the Helmick Road Reservation established in 1981.

  13. 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.

  14. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    SciTech Connect (OSTI)

    Jha, M.C.; Berggren, M.H.

    1987-10-27

    AMAX Research Development Center (AMAX R D) has been investigating methods for improving the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hog coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. The reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point in a bench-scale fixed-bed reactor. The durability may be defined as the ability of the sorbent to maintain its reactivity and other important physical characteristics such as size, strength, and specific surface area during 10 cycles of sulfidation and regeneration. Two base case sorbents, spherical pellets and cylindrical extrudes used in related METC sponsored projects, are being used to provide a basis for the comparison of physical characteristics and chemical reactivity.

  15. Band gap narrowing in zinc oxide-based semiconductor thin films...

    Office of Scientific and Technical Information (OSTI)

    ABSORPTION; ALUMINIUM COMPOUNDS; BORON COMPOUNDS; CHARGE CARRIERS; CONCENTRATION RATIO; DENSITY; DOPED MATERIALS; ELECTRONIC STRUCTURE; ENERGY GAP; GALLIUM COMPOUNDS; INDIUM...

  16. Development of silver and zinc oxide decorated nanoclay containing polymeric composites for water disinfection applications

    SciTech Connect (OSTI)

    Motshekga, Sarah C.; Ray, Suprakas Sinha; Momba, Maggie N. B.

    2015-05-22

    Contaminated drinking water has serious implications to the human health that could lead to death. The rapid growth of bacterial contamination in drinking water is alarming, and yet a robust and cost effective method with less limitation has not been developed. The current study is aimed at evaluating the performance of nanoclay composites dispersed in chitosan biopolymer as an antibacterial material. The performances of the composites were evaluated using the batch kinetic studies. Three composites of Ag-CtsB, ZnO-CtsB and Ag/ZnO-CtsB were prepared and evaluated against gram negative Escherichia coli and gram positive Enterococcus faecalis bacteria. The composites were characterized by powder X-ray diffraction, scanning electron microscope, energy dispersive spectroscopy and BET surface area measurements. Antibacterial activity results showed that the composites can be a potent bactericide material for water disinfection as they are highly effective against both gram negative and gram positive bacteria tested. Whereas both Ag-CtsB and ZnO-CtsB composites showed good antibacterial activity against bacteria with removal efficiency from 51%, best antibacterial activity was observed with Ag/ZnO-CtsB composite with removal efficiency from 78%. The results revealed that Ag/ZnO-CtsB composite is a promising bactericide that is highly effective against both gram negative and gram positive bacteria tested.

  17. Highly Efficient Selective Hydrogenation of Cinnamaldehyde to Cinnamyl Alcohol over Gold Supported on Zinc Oxide Materials

    SciTech Connect (OSTI)

    Chen, Hangning; Cullen, David A.; Larese, J. Z.

    2015-11-30

    We used Au/ZnO catalysts for liquid-phase selective hydrogenation of cinnamaldehyde to cinnamyl alcohol and compared with Au/Fe2O3 catalysts. To investigate the influence of the support on the hydrogenation activity and selectivity, three different Au/ZnO catalysts were synthesized, including Au/rod-tetrapod ZnO, Au/porous ZnO, and Au/ZnO-CP prepared using a coprecipitation method. Moreover, the influence of calcination temperature was also systematically investigated in this study. The characterization of Au/ZnO catalysts was performed using ICP, N2 adsorption/desorption isotherms, X-ray diffraction, scanning transmission electron microscopy, and X-ray photoelectron spectroscopy. Among all the supported Au catalysts prepared in this study, Au/ZnO-CP exhibits both the highest hydrogenation activity and selectivity. Using a 1.5% Au/ZnO-CP catalyst, 100% selectivity could be achieved with 94.9% conversion. Finally, we find that the Au particle (size and shape), the ZnO support (size and surface texture) and the interaction between Au and ZnO are three important parameters for achieving a highly efficient Au/ZnO catalyst.

  18. Highly Efficient Selective Hydrogenation of Cinnamaldehyde to Cinnamyl Alcohol over Gold Supported on Zinc Oxide Materials

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

    Chen, Hangning; Cullen, David A.; Larese, J. Z.

    2015-11-30

    We used Au/ZnO catalysts for liquid-phase selective hydrogenation of cinnamaldehyde to cinnamyl alcohol and compared with Au/Fe2O3 catalysts. To investigate the influence of the support on the hydrogenation activity and selectivity, three different Au/ZnO catalysts were synthesized, including Au/rod-tetrapod ZnO, Au/porous ZnO, and Au/ZnO-CP prepared using a coprecipitation method. Moreover, the influence of calcination temperature was also systematically investigated in this study. The characterization of Au/ZnO catalysts was performed using ICP, N2 adsorption/desorption isotherms, X-ray diffraction, scanning transmission electron microscopy, and X-ray photoelectron spectroscopy. Among all the supported Au catalysts prepared in this study, Au/ZnO-CP exhibits both the highest hydrogenationmore » activity and selectivity. Using a 1.5% Au/ZnO-CP catalyst, 100% selectivity could be achieved with 94.9% conversion. Finally, we find that the Au particle (size and shape), the ZnO support (size and surface texture) and the interaction between Au and ZnO are three important parameters for achieving a highly efficient Au/ZnO catalyst.« less

  19. Structural and optical properties of chromium doped zinc oxide nanoparticles synthesized by sol-gel method

    SciTech Connect (OSTI)

    Naqvi, Syed Mohd. Adnan; Irshad, Kashif; Soleimani, Hassan E-mail: noorhana-yahya@petronas.com.my; Yahya, Noorhana E-mail: noorhana-yahya@petronas.com.my

    2014-10-24

    Nanosized Cr-doped ZnO nano particles were synthesized by facile sol-gel auto combustion method. The structural and optical properties of Cr-doped ZnO nanoparticles have been investigated by XRD and UV-Vis spectroscopy at room temperature for 0% to 8% concentration. X-ray diffraction analysis reveals that the Cr-doped ZnO crystallizes in a single phase polycrystalline nature with wurtzite lattice. With every % of doping, the peaks are shifting scarcely and doping of Cr is possible up to 7%. After that, the last peak vanishes, that signifies its structure is transmuted from 8% doping. The average crystallite size decreases with increase in Cr concentration (i.e. 28.9 nm for 0% to 25.8 nm for 8%). The UV-Vis spectra of the nanoparticles betoken an incrementation in the band gap energy from 3.401, 3.415, 3.431, 3.437,3.453, 3.514,3.521, 3.530 and 3.538 eV respectively, for 0,1, 2, 3, 4, 5, 6, 7 and 8 % doping concentration.

  20. Preparation and characterization of indium zinc oxide thin films by electron beam evaporation technique

    SciTech Connect (OSTI)

    Keshavarzi, Reza [Chemistry Department, Catalysis Division, University of Isfahan, Isfahan 81746-73441 (Iran, Islamic Republic of)] [Chemistry Department, Catalysis Division, University of Isfahan, Isfahan 81746-73441 (Iran, Islamic Republic of); Mirkhani, Valiollah, E-mail: mirkhani@sci.ui.ac.ir [Chemistry Department, Catalysis Division, University of Isfahan, Isfahan 81746-73441 (Iran, Islamic Republic of)] [Chemistry Department, Catalysis Division, University of Isfahan, Isfahan 81746-73441 (Iran, Islamic Republic of); Moghadam, Majid, E-mail: moghadamm@sci.ui.ac.ir [Chemistry Department, Catalysis Division, University of Isfahan, Isfahan 81746-73441 (Iran, Islamic Republic of) [Chemistry Department, Catalysis Division, University of Isfahan, Isfahan 81746-73441 (Iran, Islamic Republic of); Department of Nanotechnology Engineering, University of Isfahan, Isfahan 81746-73441 (Iran, Islamic Republic of); Tangestaninejad, Shahram; Mohammadpoor-Baltork, Iraj [Chemistry Department, Catalysis Division, University of Isfahan, Isfahan 81746-73441 (Iran, Islamic Republic of)] [Chemistry Department, Catalysis Division, University of Isfahan, Isfahan 81746-73441 (Iran, Islamic Republic of); Fallah, Hamid Reza; Dastjerdi, Mohammad Javad Vahid; Modayemzadeh, Hamed Reza [Department of Physics, University of Isfahan, Isfahan 81746-73441 (Iran, Islamic Republic of)] [Department of Physics, University of Isfahan, Isfahan 81746-73441 (Iran, Islamic Republic of)

    2011-04-15

    In this work, the preparation of In{sub 2}O{sub 3}-ZnO thin films by electron beam evaporation technique on glass substrates is reported. Optical and electrical properties of these films were investigated. The effect of dopant amount and annealing temperature on the optical and electrical properties of In{sub 2}O{sub 3}-ZnO thin films was also studied. Different amount of ZnO was used as dopant and the films were annealed at different temperature. The results showed that the most crystalline, transparent and uniform films with lowest resistivity were obtained using 25 wt% of ZnO annealed at 500 {sup o}C.

  1. Durable zinc oxide containing sorbents for moving bed and fluid-bed applications

    SciTech Connect (OSTI)

    Siriwardane, R.V.

    1998-12-31

    A series of novel regenerable desulfurization sorbents operational at a wide range of temperatures (260--600 C) has been developed by the in-house research staff at the US Department of Energy`s Federal Energy Technology Center. The sorbent, identified as METC10, has demonstrated very high attrition resistance as well as very high and stable reactivity conducted under numerous testing regimes under both simulated and actual fuel gas conditions. The METC10 sorbent suitable for moving bed reactor applications is the only sorbent which has exceeded all the criteria required for use in the Tampa Electric Company (TECO) Clean Coal Technology (CCT) demonstration project. The required criteria for the TECO project included, a sulfur loading of 6.7 lb/ft{sup 3} while maintaining the outlet H{sub 2}S level < 20 ppmv, attrition of < 5 wt% after 25 cycle test and regeneration under the very drastic conditions of 10% SO{sub 2} at 510 C under 5--7 atmospheres. In addition, the sorbent was also tested at temperatures ranging from 370 C to 260 C with simulated coal gas. At this low temperature, it was possible to achieve a sulfur loading > 6 lb/ft{sup 3}, indicating that the sorbent is suitable for applications over a wide range of temperatures. It was also possible to prepare METC10 sorbent suitable for fluidized/transport reactor bed applications utilizing spray drying technique. These sorbents had both high attrition resistance (> 95%) and high sulfur capacity (> 14 wt%), and showed stable reactivity during multi-cycle testing.

  2. Sonochemical synthesis and photocatalytic property of zinc oxide nanoparticles doped with magnesium(II)

    SciTech Connect (OSTI)

    Lu, Xianyong; Liu, Zhaoyue; Zhu, Ying; Jiang, Lei; Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190

    2011-10-15

    Highlights: {yields} Mg-doped ZnO nanoparticles were synthesized by sonochemical strategy. {yields} Mg-doped ZnO nanoparticles present good photocatalytic properties. {yields} The change of band gap contributes to their high efficiency in photocatalyst. -- Abstract: Mg-doped ZnO nanoparticles were successfully synthesized by sonochemical method. The products were characterized by scan electron microscopy (SEM) and X-ray powder diffraction (XRD). SEM images revealed that ZnO doped with Mg(II) nanoparticles and ZnO nanoparticles synthesized by the same strategy all had spherical topography. XRD patterns showed that the doped nanoparticles had the same crystals structures as the pure ZnO nanoparticles. The Mg-doped ZnO nanoparticles had larger lattice volume than the un-doped nanoparticles. X-ray photoelectron spectroscopy (XPS) not only demonstrated the moral ratio of Mg and Zn element on the surface of nanoparticles, but their valence in nanoparticles as well. The Mg-doped ZnO nanoparticles presented good properties in photocatalyst compared with pure ZnO nanoparticles.

  3. Prospects for the pulsed electrodeposition of zinc-oxide hierarchical nanostructures

    SciTech Connect (OSTI)

    Klochko, N. P.; Myagchenko, Y. O.; Melnychuk, E. E.; Kopach, V. R.; Klepikova, E. S.; Lyubov, V. N.; Khrypunov, G. S.; Kopach, A. V.

    2013-08-15

    Studies into the effect of the conditions of pulsed electrodeposition upon the structural and sub-structural parameters, morphology, and optical properties of ZnO-crystallite arrays make it possible to establish those parameters optimal for the formation of ZnO nanorods oriented normally to the substrate surface. These parameters are as follows: an electrolyte temperature of 70-85 Degree-Sign C, duty cycle of 40%, and a pulse-repetition frequency of 2 Hz. The nanorod dimensions can be varied by heating or cooling the electrolyte within the above-indicated limits; as a result, small-sized nanorods can be electrically deposited on the surface of larger nanorods to form hierarchical nanostructures. By varying the duty cycle, it is possible to modify the surface morphology of the arrays up to the formation of mesoporous ZnO networks. In combination with ZnO nanorods, such networks are capable of forming hierarchical nanostructures with large specific areas.

  4. Synthesis of silica coated zinc oxide-poly(ethylene-co-acrylic...

    Office of Scientific and Technical Information (OSTI)

    OSTI Identifier: 22348586 Resource Type: Journal Article Resource Relation: Journal Name: Materials Research Bulletin; Journal Volume: 51; Other Information: Copyright (c) 2013 ...

  5. Oxygen Diffusion Enables Anti-Wear Boundary Film Formation on Titanium Surfaces in Zinc-Dialkyl-Dithiophosphate (ZDDP)-Containing Lubricants

    SciTech Connect (OSTI)

    Qu, Jun; Blau, Peter Julian; Howe, Jane Y; Meyer III, Harry M

    2009-01-01

    This paper reports a wear reduction by up to six orders of magnitude for Ti-6Al-4V alloy when treated by an oxygen diffusion (OD) process and subsequently tested in a zinc-dialkyl-dithiophosphate (ZDDP)-containing lubricant. In addition to case hardening, it is discovered that OD enables the formation of an anti-wear boundary film on the titanium surface. Transmission electron microscopy and surface chemical analyses revealed that this boundary film has a two-layer structure comprising an amorphous oxide interlayer and a ZDDP-based top film with complex compounds.

  6. Sessile drop studies on polybromide/zinc-bromine battery electrolyte

    SciTech Connect (OSTI)

    Kinoshita, K.; Leach, S.C.

    1982-08-01

    Improvements in the performance of zinc-bromine batteries have been observed with electrolytes containing a quaternary ammonium salt that complexes the bromine to reduce the concentration of free bromine in solution. A variety of quaternary ammonium salts that complex bromine to form a so-called polybromide oil have been considered. Various papers have discussed measurements of the physicochemical properties of the two-component system of bromine-quaternary ammonium bromide in an aqueous medium. The purpose of this paper is to investigate the interfacial tension of polybromide oils on the electrolytes for zinc-bromine batteries by reporting a study of the interfacial tension and contact angle of polybromide oil drops in which the sessile drop method is used. The interfacial tensions for the polybromide phases are found to be considerably lower than the values commonly reported for two-phase systems containing organic and aqueous phases. However, several two-phase systems, such as benzyl alcohol/water, furfural/water, and ethyl acetate/water have low interfacial tension comparable to that of the polybromide/electrolyte system. The low interfacial tension of the polybromide oil phase has important practical implications for the zinc-bromine battery. A stable emulsion can be produced very readily; small drops of the polybromide-oil phase can thus be stabilized with the electrolyte phase and can be expected to enhance the mass transfer of bromine from the polybromide to the electrode.

  7. Application of Developed APCVD Transparent Conducting Oxides and Undercoat Technologies for Economical OLED Lighting

    SciTech Connect (OSTI)

    Gary Silverman; Bluhm, Martin; Coffey, James; Korotkov, Roman; Polsz, Craig; Salemi, Alexandre; Smith, Robert; Smith, Ryan; Stricker, Jeff; Xu,Chen; Shirazi, Jasmine; Papakonstantopulous, George; Carson, Steve Philips Lighting GmbH Goldman, Claudia; Hartmann, Sren; Jessen, Frank; Krogmann, Bianca; Rickers, Christoph; Ruske, Manfred, Schwab, Holger; Bertram, Dietrich

    2011-01-02

    Economics is a key factor for application of organic light emitting diodes (OLED) in general lighting relative to OLED flat panel displays that can handle high cost materials such as indium tin oxide (ITO) or Indium zinc oxide (IZO) as the transparent conducting oxide (TCO) on display glass. However, for OLED lighting to penetrate into general illumination, economics and sustainable materials are critical. The issues with ITO have been documented at the DOE SSL R&D and Manufacturing workshops for the last 5 years and the issue is being exaserbated by export controls from China (one of the major sources of elemental indium). Therefore, ITO is not sustainable because of the fluctuating costs and the United States (US) dependency on other nations such as China. Numerous alternatives to ITO/IZO are being evaluated such as Ag nanoparticles/nanowires, carbon nanotubes, graphene, and other metal oxides. Of these other metal oxides, doped zinc oxide has attracted a lot of attention over the last 10 years. The volume of zinc mined is a factor of 80,000 greater than indium and the US has significant volumes of zinc mined domestically, resulting in the ability for the US to be self-sufficient for this element that can be used in optoelectonic applications. The costs of elemental zinc is over 2 orders of magnitude less than indium, reflecting the relative abundance and availablility of the elements. Arkema Inc. and an international primary glass manufacturing company, which is located in the United States, have developed doped zinc oxide technology for solar control windows. The genesis of this DOE SSL project was to determine if doped zinc oxide technology can be taken from the commodity based window market and translate the technology to OLED lighting. Thus, Arkema Inc. sought out experts, Philips Lighting, Pacific Northwest National Laboratories (PNNL) and National Renewable Research Laboratories (NREL), in OLED devices and brought them into the project. This project had a

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

    SciTech Connect (OSTI)

    Toroker, Maytal; Carter, Emily A.

    2013-02-21

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

  9. Studies on photocatalytic activity of zinc ferrite catalysts synthesized by shock waves

    SciTech Connect (OSTI)

    Liu, J; Lu, G.; Xu, T.; Xu, K.; He, H.; Tan, H.

    1996-09-01

    The photocatalytic activity in the photodehydrogenation of H{sub 2}S of zinc ferrites synthesized by shock wave loading is investigated and compared with that of zinc ferrites prepared by calcination. It is shown that photocatalytic activity of zinc ferrites prepared by shock wave treatment is much higher and that this activity increases with the increase of shock wave pressure. XRD, TEM, and electron diffraction methods were used to characterize the catalysts. Possible reasons for the enhancement of photocatalytic activity are discussed.

  10. Electronic and structural characteristics of zinc-blende wurtzite biphasic homostructure GaN nanowires

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

    Jacobs, Benjamin W.; Ayres, Virginia M.; Petkov, Mihail P.; Halpern, Joshua B.; He, Maoqi; Baczewski, Andrew D.; McElroy, Kaylee; Crimp, Martin A.; Zhang, Jiaming; Shaw, Harry C.

    2016-02-01

    Here, we report a new biphasic crystalline wurtzite/zinc-blende homostructure in gallium nitride nanowires. Cathodoluminescence was used to quantitatively measure the wurtzite and zinc-blende band gaps. High-resolution transmission electron microscopy was used to identify distinct wurtzite and zinc-blende crystalline phases within single nanowires through the use of selected area electron diffraction, electron dispersive spectroscopy, electron energy loss spectroscopy, and fast Fourier transform techniques. A mechanism for growth is identified.

  11. Hydrocracking with molten zinc chloride catalyst containing 2-12% ferrous chloride

    DOE Patents [OSTI]

    Zielke, Clyde W.; Bagshaw, Gary H.

    1981-01-01

    In a process for hydrocracking heavy aromatic polynuclear carbonaceous feedstocks to produce hydrocarbon fuels boiling below about 475.degree. C. by contacting the feedstocks with hydrogen in the presence of a molten zinc chloride catalyst and thereafter separating at least a major portion of the hydrocarbon fuels from the spent molten zinc chloride catalyst, an improvement comprising: adjusting the FeCl.sub.2 content of the molten zinc chloride to from about 2 to about 12 mol percent based on the mixture of ferrous chloride and molten zinc chloride.

  12. Regeneration and Durability of Advanced Zinc Ferrite Sorbent for Hot Coal Gas Desulfurization

    SciTech Connect (OSTI)

    Shirai, H.; Kobayashi, M.; Nunokawa, M.; Noda, N.

    2002-09-19

    In this study, we investigate the regeneration characteristics, desulfurization performance after regeneration and the durability of zinc ferrite sorbent in the desulfurization/regeneration cycles.

  13. Growth control of the oxidation state in vanadium oxide thin...

    Office of Scientific and Technical Information (OSTI)

    Growth control of the oxidation state in vanadium oxide thin films Prev Next Title: Growth control of the oxidation state in vanadium oxide thin films Authors: Lee, Shinbuhm ...

  14. Geothermometry At Upper Hot Creek Ranch Area (Benoit & Blackwell...

    Open Energy Info (EERE)

    Activity Details Location Upper Hot Creek Ranch Area Exploration Technique Geothermometry Activity Date Usefulness useful DOE-funding Unknown Notes Ten water samples were collected...

  15. An Integrated Geophysical Analysis Of The Upper Crust Of The...

    Open Energy Info (EERE)

    on upper crustal structure. We used results from surface geological mapping, drill hole data from water wells and geothermal exploration wells, KRISP 85 seismic data for a...

  16. UPPER BOUND ON THE FIRST STAR FORMATION HISTORY (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    Citation Details In-Document Search Title: UPPER BOUND ON THE FIRST STAR FORMATION HISTORY Our understanding of the nature of the extragalactic background light (EBL) has improved ...

  17. Upper Midwest Hydrogen Initiative UMHI | Open Energy Information

    Open Energy Info (EERE)

    Midwest Hydrogen Initiative UMHI Jump to: navigation, search Name: Upper Midwest Hydrogen Initiative (UMHI) Place: Minneapolis, Minnesota Zip: 55407 Product: An industry-led,...

  18. In-situ growth of zinc tungstate nanorods on graphene for enhanced photocatalytic performance

    SciTech Connect (OSTI)

    Rao, Lei; Xu, Junling; Ao, Yanhui; Wang, Peifang

    2014-09-15

    Graphical abstract: Graphene/ZnWO{sub 4} (GZnWO{sub 4}) nanorod composite photocatalysts were prepared by a simple one-step method. Namely, the reduction of graphene oxide and the growth of ZnWO{sub 4} nanorod occurred simultaneously in one single process. An enhancement in the photocatalytic activities were observed in GZnWO{sub 4} composites compared with pure ZnWO{sub 4} under UV light irradiation. - Highlights: GrapheneZnWO{sub 4} composite photocatalyst was prepared for the first time. The as-prepared composite photocatalysts show high activity for dye degradation. Effect of graphene amount on the photocatalytic activity was investigated. - Abstract: Graphenezinc tungstate (GZnWO{sub 4}) hybrid photocatalysts were prepared by an in-situ growth method in which the reduction of graphene oxide (GO) and the growth of ZnWO{sub 4} crystals occurred simultaneously. The materials were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, UVvis diffuse reflectance spectroscopy and X-ray photoelectron spectroscopy. The photocatalytic activity was investigated by the degradation of dye methylene blue (MB). An enhancement in the photocatalytic activity was observed for GZnWO{sub 4} hybrids compared with pure ZnWO{sub 4} under UV light. This improvement was attributed to the following two reasons: increased migration efficiency of photo-induced electrons and increased adsorption activity for dye molecules. The effect of the amount of graphene on the photocatalytic activity was also investigated. Results showed that there was an optimum amount of 2%.

  19. Upper atmospheric effects of the hf active auroral research program ionospheric research instrument (HAARP IRI)

    SciTech Connect (OSTI)

    Eccles, V.; Armstrong, R.

    1993-05-01

    The earth's ozone layer occurs in the stratosphere, primarily between 10 and 30 miles altitude. The amount of ozone, O3, present is the result of a balance between production and destruction processes. Experiments have shown that natural processes such as auroras create molecules that destroy O. One family of such molecules is called odd nitrogen of which nitric oxide (NO) is an example. Because the HAARP (HF Active Auroral Research Program) facility is designed to mimic and investigate certain natural processes, a study of possible effects of HAARP on the ozone layer was conducted. The study used a detailed model of the thermal and chemical effects of the high power HF beam, which interacts with free electrons in the upper atmosphere above 50 miles altitude. It was found only a small fraction of the beam energy goes into the production of odd nitrogen molecules, whereas odd nitrogen is efficiently produced by auroras. Since the total energy emitted by HAARP in the year is some 200,000 times less than the energy deposited in the upper atmosphere by auroras, the study demonstrates that HAARP HF beam experiments will cause no measurable depletion of the earth's ozone layer.... Ozone, Ozone depletion, Ozone layer, Odd nitrogen, Nitric oxide, HAARP Emitter characteristics.

  20. Characterization and oxidation states of Cu and Pd in Pd?CuO/ZnO/ZrO[subscript 2] catalysts for hydrogen production by methanol partial oxidation

    SciTech Connect (OSTI)

    Schuyten, S.; Guerrero, S.; Miller, J.T.; Shibatae, T.; Wolf, E.E.

    2009-01-30

    Copper and zinc oxide based catalysts prepared by coprecipitation were promoted with palladium and ZrO{sub 2}, and their activity and selectivity for methanol oxidative reforming was measured and characterized by N{sub 2}O decomposition, X-ray absorption spectroscopy, BET, X-ray photoelectron spectroscopy, X-ray diffraction, and temperature programmed reduction. Addition of ZrO{sub 2} increased copper dispersion and surface area, with little effect on activity, while palladium promotion significantly enhanced activity with little change of the catalytic structure. A catalyst promoted with both ZrO{sub 2} and palladium yielded hydrogen below 150 C. EXAFS results under reaction conditions showed that the oxidation state of copper was influenced by palladium in the catalyst bulk. A palladium promoted catalyst contained 90% Cu{sup 0}, while the copper in an unpromoted catalyst was 100% Cu{sup 1+} at the same temperature. Palladium preferentially forms an unstable alloy with copper instead of zinc during reduction, which persists during reaction regardless of copper oxidation state. A 100-h time on stream activity measurement showed growth in copper crystallites and change in copper oxidation state resulting in decreasing activity and selectivity. A kinetic model of the reaction pathway showed that palladium and ZrO{sub 2} promoters lower the activation energy of methanol combustion and steam reforming reactions.

  1. lithium cobalt oxide cathode

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

    lithium cobalt oxide cathode - Sandia Energy Energy Search Icon Sandia Home Locations ... SunShot Grand Challenge: Regional Test Centers lithium cobalt oxide cathode Home...

  2. Chemical Vapor Deposited Zinc Sulfide. SPIE Press Monograph

    SciTech Connect (OSTI)

    McCloy, John S.; Tustison, Randal W.

    2013-04-22

    Zinc sulfide has shown unequaled utility for infrared windows that require a combination of long-wavelength infrared transparency, mechanical durability, and elevated-temperature performance. This book reviews the physical properties of chemical vapor deposited ZnS and their relationship to the CVD process that produced them. An in-depth look at the material microstructure is included, along with a discussion of the material's optical properties. Finally, because the CVD process itself is central to the development of this material, a brief history is presented.

  3. An algebraic model for a zinc/bromine flow cell

    SciTech Connect (OSTI)

    Simpson, G.D.; White, R.E. . Dept. of Chemical Engineering)

    1989-08-01

    An algebraic model for a parallel plate, zinc/bromine flow cell is presented and used to predict various performance quantities, which are compared to those predicted by using previously published differential equation models. The results presented compare well with previous work. The model is based on the concept of using well-mixed zones and linear concentration and potential profiles for the diffusion layers and the separator. The Butler-Volmer equation is used for the electro chemical reactions, and the homogeneous reaction between bromine and bromide is included.

  4. Recent progress on Exxon's circulating zinc bromine battery system

    SciTech Connect (OSTI)

    Bellows, R.J.

    1981-01-01

    The design, performance, and factory cost of Exxon's circulating zinc bromine batteries are described. The Exxon system has demonstrated stable performance in scale-ups to 3- and 10-kWh sub-modules. Cost studies based on recently demonstrated extrusion and injection molding techniques, have shown that this battery, with plastic electrodes, bipolar stacks, Br/sub 2/ complexation, and circulating electrolytes, could be produced (20 kWh units, 100,000 units/year) at a factory cost of $28/kWh (excluding R.O.I., and various indirect overheads).

  5. Laser Raman spectroscopy study of the zinc and bromide ion complex equilibrium in zinc/bromine battery electrolytes. [2M ZnBr/sub 2/ and 1M KBr solution

    SciTech Connect (OSTI)

    Grimes, P.G.; Larrabee, J.A.

    1985-01-01

    Laser Raman spectroscopy was used to study the zinc and bromide ion complex equilibrium in zinc bromine battery model electrolytes. Solutions of zinc bromide with added KBr, HBr and N-methyl, N-ethyl morpholinium (MEM) bromide were examined and compared. Solutions studied ranged from 1 to 3 molar in zinc and from 2.5 to 8 molar in bromide. A typical Raman spectrum of a zinc bromide solution is shown in Figure 1. Each of the zinc species is identified, Zn/sup + +/ (aq), ZnBr/sup +/, ZnBr/sub 2/ (aq), ZnBr/sub 3//sup -/ and ZnBr/sub 4//sup 2 -/. By the use of peak heights or deconvolution/integration along with published Raman cross sections, the amount of each zinc species could be quantitatively determined. The addition of bromide ions to the zinc bromide solutions will shift the equilibrium toward higher bromide complexes. The added cations will influence the shifts. It has been noted that the conductivity of the electrolyte decreases when the quaternary ammonium ions are present compared to cations such as potassium or hydrogen. Significantly more free zinc is present in zinc bromide solutions with added KBr than with either MEMBr or HBr. Shifts are also noted with the other zinc ion containing species. It appears that the quaternary ammonium ions and possibly the pH could have a stabilizing effect on zinc bromide complex ion formation. 2 figs.

  6. Upper Subcritical Calculations Based on Correlated Data

    SciTech Connect (OSTI)

    Sobes, Vladimir; Rearden, Bradley T; Mueller, Don; Marshall, William BJ J; Scaglione, John M; Dunn, Michael E

    2015-01-01

    The American National Standards Institute and American Nuclear Society standard for Validation of Neutron Transport Methods for Nuclear Criticality Safety Calculations defines the upper subcritical limit (USL) as “a limit on the calculated k-effective value established to ensure that conditions calculated to be subcritical will actually be subcritical.” Often, USL calculations are based on statistical techniques that infer information about a nuclear system of interest from a set of known/well-characterized similar systems. The work in this paper is part of an active area of research to investigate the way traditional trending analysis is used in the nuclear industry, and in particular, the research is assessing the impact of the underlying assumption that the experimental data being analyzed for USL calculations are statistically independent. In contrast, the multiple experiments typically used for USL calculations can be correlated because they are often performed at the same facilities using the same materials and measurement techniques. This paper addresses this issue by providing a set of statistical inference methods to calculate the bias and bias uncertainty based on the underlying assumption that the experimental data are correlated. Methods to quantify these correlations are the subject of a companion paper and will not be discussed here. The newly proposed USL methodology is based on the assumption that the integral experiments selected for use in the establishment of the USL are sufficiently applicable and that experimental correlations are known. Under the assumption of uncorrelated data, the new methods collapse directly to familiar USL equations currently used. We will demonstrate our proposed methods on real data and compare them to calculations of currently used methods such as USLSTATS and NUREG/CR-6698. Lastly, we will also demonstrate the effect experiment correlations can have on USL calculations.

  7. Use of underpotential deposition of zinc to mitigate hydrogen absorption into Monel K500

    SciTech Connect (OSTI)

    Zheng, G.; Popov, B.N.; White, R.E. . Dept. of Chemical Engineering)

    1994-05-01

    Polarization experiments and a potentiostatic pulse technique have been used to show that a monolayer coverage of zinc effectively inhibits the absorption of hydrogen into Monel K500. By depositing a monolayer of zinc on Monel K500 the hydrogen, evolution reaction and hydrogen ingress flux rate were reduced by 60%.

  8. Thermal-sprayed zinc anodes for cathodic protection of steel-reinforced concrete bridges

    SciTech Connect (OSTI)

    Bullard, Sophie J.; Covino, Bernard S., Jr.; Cramer, Stephen D.; McGill, Galen E.

    1996-01-01

    Thermal-sprayed zinc anodes are being used in Oregon in impressed current cathodic protection (ICCP) systems for reinforced concrete bridges. The U.S. Department of Energy, Albany Research Center, is collaborating with the Oregon Department of Transportation (ODOT) to evaluate the long-term performance and service life of these anodes. Laboratory studies were conducted on concrete slabs coated with 0.5 mm (20 mil) thick, thermal-sprayed zinc anodes. The slabs were electrochemically aged at an accelerated rate using an anode current density of 0.032 A/m2 (3mA/ft2). Half the slabs were preheated before thermal-spraying with zinc; the other half were unheated. Electrochemical aging resulted in the formation at the zinc-concrete interface of a thin, low pH zone (relative to cement paste) consisting primarily of ZnO and Zn(OH)2, and in a second zone of calcium and zinc aluminates and silicates formed by secondary mineralization. Both zones contained elevated concentrations of sulfate and chloride ions. The original bond strength of the zinc coating decreased due to the loss of mechanical bond to the concrete with the initial passage of electrical charge (aging). Additional charge led to an increase in bond strength to a maximum as the result of secondary mineralization of zinc dissolution products with the cement paste. Further charge led to a decrease in bond strength and ultimately coating disbondment as the interfacial reaction zones continued to thicken. This occurred at an effective service life of 27 years at the 0.0022 A/m2 (0.2 mA/ft2) current density typically used by ODOT in ICCP systems for coastal bridges. Zinc coating failure under tensile stress was primarily cohesive within the thickening reaction zones at the zinc-concrete interface. There was no difference between the bond strength of zinc coatings on preheated and unheated concrete surfaces after long service times.

  9. Photo-oxidation catalysts

    DOE Patents [OSTI]

    Pitts, J. Roland; Liu, Ping; Smith, R. Davis

    2009-07-14

    Photo-oxidation catalysts and methods for cleaning a metal-based catalyst are disclosed. An exemplary catalyst system implementing a photo-oxidation catalyst may comprise a metal-based catalyst, and a photo-oxidation catalyst for cleaning the metal-based catalyst in the presence of light. The exposure to light enables the photo-oxidation catalyst to substantially oxidize absorbed contaminants and reduce accumulation of the contaminants on the metal-based catalyst. Applications are also disclosed.

  10. Oxidation of coal and coal pyrite mechanisms and influence on surface characteristics

    SciTech Connect (OSTI)

    Doyle, F.M.

    1992-01-01

    During the ninth quarter, electrochemical experiments were done on electrodes prepared from Upper Freeport coal pyrite and Pittsburgh coal pyrite samples provided by the US Bureau of Mines, Pittsburgh Research Center, Pennsylvania. Scanning electron microscopy and energy dispersive X-ray analysis were done to characterize the morphology and composition of the surface of as-received coal, oxidized coal and coal pyrite. In addition, electrokinetic tests were done on Upper Freeport coal pyrite.