000053511 001__ 53511
000053511 005__ 20190316233513.0
000053511 0247_ $$2doi$$a10.1179/096797804225018688
000053511 02470 $$2DAR$$a5793
000053511 02470 $$2ISI$$a000224295500001
000053511 037__ $$aARTICLE
000053511 245__ $$aInfluence of microstructure on oxygen transport in perovskite type membranes
000053511 269__ $$a2004
000053511 260__ $$c2004
000053511 336__ $$aJournal Articles
000053511 520__ $$aThe effect of the bulk microstructure (grain size distribution, grain boundary length) on the oxygen transport properties of permeation membranes is investigated in this work. For this purpose, La0.5Sr0.5FeO3-? samples with different microstructures have been prepared by modifying the sintering duration and/or temperature. The average grain sizes, ranging from 0.20 to 1.43 micron, were determined from SEM analysis. The oxygen transport properties of these samples were characterised by permeation measurement as a function of temperature in an air/argon oxygen partial pressure gradient. The fluxes presented a change in the activation energy which was attributed to a change in the rate limiting step, from bulk diffusion at lower temperature (<850°C) to surface limitation at higher temperature (>900°C). Only the transport through the bulk was influenced by the microstructure, with the highest flux for the smallest grains. At 800°C, the fluxes were respectively 0.06, 0.03 and 0.01 micromol/cm2s through 1 mm thick samples of average grain sizes of 0.20, 0.63 and 1.43 micron, respectively. This would imply that oxygen transport occurs more rapidly along the grain boundaries than through the bulk. Grain boundary structure and composition were analysed by TEM.
000053511 6531_ $$amixed conducting oxides
000053511 6531_ $$agrain size
000053511 6531_ $$agrain boundary lenght
000053511 6531_ $$alenisystem
000053511 6531_ $$apermeation membranes
000053511 6531_ $$aoxygen transport
000053511 700__ $$0241617$$g101146$$aDiethelm, Stefan
000053511 700__ $$0240166$$g107971$$aVan herle, Jan
000053511 700__ $$aBuffat, Philippe$$0240619$$g104664
000053511 700__ $$aSfeir, Joseph
000053511 773__ $$j103$$tBritish Ceramic Transactions$$k4$$q147-152
000053511 8564_ $$zURL
000053511 8564_ $$uhttps://infoscience.epfl.ch/record/53511/files/Diethelm_BritCeramTrans2004.pdf$$zn/a$$s400439
000053511 909C0 $$xU10315$$0252044$$pLENI
000053511 909C0 $$0252025$$pCIME$$xU10192
000053511 909CO $$qGLOBAL_SET$$pSB$$pSTI$$particle$$ooai:infoscience.tind.io:53511
000053511 937__ $$aLENI-ARTICLE-2004-019
000053511 970__ $$aLENI-ARTICLE-2004-019/LENI
000053511 973__ $$rREVIEWED$$sPUBLISHED$$aEPFL
000053511 980__ $$aARTICLE