Results 211 to 220 of about 6,585 (256)

Surface Oxygen Exchange Kinetics of Solid Oxide Ion Conductors

1993
For oxides with high oxygen ion mobility the exchange of lattice oxygen at the surface with ambient molecular oxygen is modelled with a simple global two step model. The first global step describes the dissociative adsorption reaction chain, while the second step describes the exchange of adsorbed mono-atomic oxygen species with the lattice oxygen.
Boukamp, Bernard A., Vinke, I.C., de Vries, Karel Jan, Burggraaf, Anthonie   +3 more
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Oxygen diffusion mechanism in the mixed ion-electron conductor NdBaCo2O5+x

Journal of Materials Chemistry, 2012
Double perovskite cobaltites were recently presented as promising cathode materials for solid oxide fuel cells. While an atomistic mechanism was proposed for oxygen diffusion in this family of materials, no direct experimental proof has been presented so far.
Hu, Y., Hernandez, Olivier, Broux, T., Bahout, Mona, Hermet, J., Ottochian, Alistar, Ritter, C., Geneste, G., Dezanneau, G.   +8 more
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Transformation of an oxygen ion conductor to a proton conductor by solid state reaction

Solid State Ionics, 2005
Abstract It is shown that starting from a thin, gas tight layer of an oxygen ion conductor such as 8YSZ a thin, gas tight layer of a proton conductor can be obtained by coating the original layer with BaCO 3 or BaO followed by sintering. Generally, a homogeneous Zr 1– x Y x O 2– y ceramic compound will react with BaO to form the desired proton ...
openaire   +1 more source

Dynamics of Mobile Oxygen Ions in Disordered Pyrochlore-Type Oxide-Ion Conductors

Defect and Diffusion Forum, 2009
We investigate the effect of cation size in the dc activation energy needed for oxygen ion conductivity, Edc, in highly disordered pyrochlore-type ionic conductors A2B2O7. Twenty compositions of general formula Ln2Zr2-yTiyO7 (Ln = Y, Dy and Gd) and Gd2-yLayZr2O7, were prepared by mechanical milling and their electrical properties measured by using ...
M.R. Díaz-Guillén, Karla J. Moreno, J.A. Díaz-Guillén, A.F. Fuentes, J. Garcia-Barriocanal, J. Santamaría, C. Leon   +6 more
openaire   +1 more source

The Kinetics of Ordering in Gadolinium Zirconate: an Unusual Oxygen Ion Conductor

MRS Proceedings, 1995
ABSTRACTGadolinium zirconate, Gd2Zr2O7, undergoes an order-disorder transition at ∼1550°C, transforming from a defect fluorite structure (Fm3m) to a pyrochlore structure (Fd3m). Both cations and anions are ordered in the low-temperature, pyrochlore structure.
Sossina M. Haile, Scott Meilicke
openaire   +1 more source

Characterisation, conductivity and mechanical properties of the oxygen-ion conductor La0.9Sr0.1Ga0.8 Mg0.2O3−x

Journal of Materials Chemistry, 1997
The new oxygen-ion conductor LaSrGaMgO has been prepared by conventional solid-state reaction at high temperatures and characterised by X-ray diffraction, scanning and transmission electron microscopy, and conductivity (four-probe dc and impedance) measurements. The room-temperature structure is orthorhombic, space group Pnma (no.
Drennan, John, Zelizko, Viktor, Hay, David, Ciacchi, Fabio T., Rajendran, S., Badwal, Sukhvinder P. S.   +5 more
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Oxygen Ion and Mixed Conductors and their Technological Applications

2000
Fundamentals. Solid State Electrochemical Cells I. Riess. Electrode Processes in Solid Oxide Fuel Cells I. Riess. Defects and Transport: Implications for Solid Oxide Electrolytes and Mixed Conductors H.L. Tuller. Interfaces J. Maier. Electrocatalysis, Catalysis and Electrochemical Promotion in Solid Electrolyte Cells C.G. Vayenas, S.I.
openaire   +1 more source

A novel titanate-based oxygen ion conductor: Gd2Ti2O7

Solid State Ionics, 1995
Abstract Electrical conductivity measurements are reported on the rare-earth pyrochlore compound Gd2Ti2O7 as a function of temperature, oxygen partial pressure and aliovalent dopant concentration. Doping experiments were performed on both the Gd and Ti cation sublattices with doping levels of 0.0 to 15.0 mol% cation substitution.
openaire   +1 more source

Fluorine-doped oxygen-ion conductors based on perovskite Ba4In2Zr2O11

Journal of Fluorine Chemistry, 2018
Abstract The effect of fluorine doping on the transport properties of perovskite-related complex oxides based on oxygen-ion conductor Ba4In2Zr2O11 is analyzed. It was shown that fluorine doping allows to increase the oxygen-ion conductivity in the region of low fluorine concentrations due to the result of increase in the mobility of the current ...
N. Tarasova, I. Animitsa
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Synthesis and Characterization of Bi0.85−xCa0.15ZrxO1.5−δ Oxygen Ion Conductors

Journal of Electronic Materials, 2018
Bi0.85−xCa0.15ZrxO1.5−δ (0.12 ≤ x ≤ 0.24) oxygen ion conductors were synthesized by solid-state reaction method. Small quantities of CaZrO3 and Ca0.15Zr0.85O0.85 second phases were observed on the grain boundaries of the Bi0.85−xCa0.15ZrxO1.5−δ matrix with cubic fluorite structure. The lattice parameter a of Bi0.85−xCa0.15ZrxO1.5−δ lay within the range
I-Ming Hung, Yu-Ting Chiou, Yi-Hung Wang, Tai-Nan Lin   +3 more
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