authors |
Kharton, VV; Kovalevsky, AV; Yaremchenko, AA; Snijkers, FMM; Cooymans, JFC; Luyten, JJ; Markov, AA; Frade, JR; Marques, FMB |
nationality |
International |
journal |
JOURNAL OF SOLID STATE ELECTROCHEMISTRY |
author keywords |
oxide composite; mixed-conducting membrane; ferrite; ceramic microstructure; oxygen permeability |
keywords |
ION-TRANSPORT; MIXED CONDUCTIVITY; MEMBRANE REACTORS; CERAMIC MEMBRANES; METHANE OXIDATION; THERMAL-EXPANSION; PERMEABILITY; CONDUCTORS; STABILITY; SYNGAS |
abstract |
Measurements of oxygen permeation through dense Sr1-x(Fe,Al)O3-delta-SrAl2O4 composite membranes showed a considerable influence of processing conditions on the surface exchange kinetics, while the bulk ambipolar conductivity is almost unaffected by microstructural factors. Compared to the materials prepared via the glycine-nitrate process (GNP), the surface limitations to oxygen transport are significantly higher for dual-phase (SrFe)(0.7)(SrAl2)(0.3)O3.3-delta made of a commercial powder synthesized by spray pyrolysis. This difference in behavior may be related to compositional inhomogeneities in the grains of A-site deficient perovskite phase and an enhanced surface concentration of grain boundaries in the case of GNP-synthesized composite, which has also smaller grain size, slightly higher thermal expansion and lower total conductivity. No essential effects on Vickers hardness, varying in the range 6.3-6.5 GPa, were found. The deposition of porous catalyst layers onto the composite surface exposed to reducing environment leads to membrane decomposition. For the fabrication of tubular membranes, the cold isostatic pressing technique was, hence, combined with mechanical treatment to increase the specific surface area without incorporation of catalytically active components. |
publisher |
SPRINGER |
issn |
1432-8488 |
year published |
2006 |
volume |
10 |
issue |
8 |
beginning page |
663 |
ending page |
673 |
digital object identifier (doi) |
10.1007/s10008-006-0141-z |
web of science category |
Electrochemistry |
subject category |
Electrochemistry |
unique article identifier |
WOS:000238326500019
|
ciceco authors
impact metrics
journal analysis (jcr 2019):
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journal impact factor |
2.646 |
5 year journal impact factor |
2.37 |
category normalized journal impact factor percentile |
50 |
dimensions (citation analysis):
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altmetrics (social interaction):
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