Transport properties and thermal expansion of perovskite-like La0.3Sr0.7Fe(Al,Cr)O3-delta ceramics

authors	Yaremchenko, AA; Kharton, VV; Shaula, AL; Patrakeev, MV; Marques, FMB
nationality	International
journal	JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
author keywords	ionic conductivity; thermal expansion; ferrites; perovskites; membranes
keywords	OXYGEN-TRANSPORT; IONIC TRANSPORT; ELECTROLYTE; PERMEATION; MEMBRANES
abstract	The use of perovskite-like (Sr,La)FeO3-delta as ceramic membrane materials requires extensive doping in order to increase stability and to suppress thermal and chemical induced expansion. The substitution of iron with aluminum and chromium in La0.3Sr0.7Fe1-x-yAlxCryO3-delta (x=0-0.4; y=0-0.2) was found to decrease total conductivity, oxygen permeability and thermal expansion coefficients. The oxygen ion transference. numbers of La0.3Sr0.7Fe(Al,Cr)O3-delta, determined by faradaic efficiency measurements in air, vary in the range 10(-4) to 10(-2) at 1073-1223 K, increasing with temperature. The incorporation of chromium into perovskite lattice enhances the low-p(O-2) stability down to oxygen partial pressures of 2 x 10(-15) to 2 x 10(-14) Pa at 1173-1223 K. The solid solution formation is, however, limited to the values of x approximate to 0.30-0.35 and y approximate to 0.07-0.08. (c) 2005 Elsevier Ltd. All rights reserved.
publisher	ELSEVIER SCI LTD
issn	0955-2219
year published	2005
volume	25
issue	12
beginning page	2603
ending page	2607
digital object identifier (doi)	10.1016/j.jeurceramsoc.2005.03.110
web of science category	Materials Science, Ceramics
subject category	Materials Science
unique article identifier	WOS:000230569300130