Properties of A-site-deficient La0.6Sr0.4Co0.2Fe0.8O3-δ-based perovskite oxides

Kostogloudis, GC; Ftikos, C

dc.contributor.author	Kostogloudis, GC	en
dc.contributor.author	Ftikos, C	en
dc.date.accessioned	2014-03-01T01:15:05Z
dc.date.available	2014-03-01T01:15:05Z
dc.date.issued	1999	en
dc.identifier.issn	0167-2738	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/13333
dc.subject	A-site-deficient perovskite oxides	en
dc.subject	SOFC cathodes	en
dc.subject	crystal structure	en
dc.subject	electrical conductivity	en
dc.subject	thermal expansion	en
dc.subject.classification	Chemistry, Physical	en
dc.subject.classification	Physics, Condensed Matter	en
dc.subject.other	Activation energy	en
dc.subject.other	Cathodes	en
dc.subject.other	Crystal lattices	en
dc.subject.other	Electric conductivity of solids	en
dc.subject.other	Fuel cells	en
dc.subject.other	Lattice constants	en
dc.subject.other	Perovskite	en
dc.subject.other	Thermal expansion	en
dc.subject.other	X ray diffraction	en
dc.subject.other	Perovskites oxides	en
dc.subject.other	Solid oxide fuel cells	en
dc.subject.other	Oxides	en
dc.title	Properties of A-site-deficient La0.6Sr0.4Co0.2Fe0.8O3-δ-based perovskite oxides	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/S0167-2738(99)00230-1	en
heal.identifier.secondary	http://dx.doi.org/10.1016/S0167-2738(99)00230-1	en
heal.language	English	en
heal.publicationDate	1999	en
heal.abstract	A-site-deficient La0.6Sr0.4Co0.2Fe0.8O3-delta-based oxides of the compositions La0.6-zSr0.4Co0.2Fe0.8O3-delta, La0.6Sr0.4-zCo0.2Fe0.8O3-delta and (La0.6Sr0.4)(1-z)Co0.2Fe0.8O3-delta (0 less than or equal to z less than or equal to 0.2) were prepared and characterized. The crystal structure, electrical conductivity and thermal expansion of these oxides were studied using X-ray diffraction, four-point DC and dilatometry, respectively. All oxides had a rhombohedral perovskite structure. The pseudo-cubic lattice parameter increased with increasing z. The electrical conductivity increased with temperature up to about 600 degrees C, and then decreased due to the loss of lattice oxygen. The charge compensation mechanism in these A-site-deficient perovskites was probably the formation of oxygen vacancies rather than the oxidation B3+ --> B4+. The conductivity decrease and the activation energy increase became more significant in the order La0.6Sr0.4-z > (La0.6Sr0.4)(1-z) > La0.6-zSr0.4. The TEC was generally lower in the A-site-deficient oxides. The lowest TEC values at 700 degrees C were 14.2, 14.1 and 13.8 X 10(-6) cm (cm degrees C)(-1) for La1-zSr0.4Co0.2Fe0.8O3-delta, with z = 0.05, and La0.6Sr0.4-zCo0.2Fe0.8O3-delta, with z = 0.1 and 0.2, respectively. (C) 1999 Elsevier Science B.V. All rights reserved.	en
heal.publisher	Elsevier Science Publishers B.V., Amsterdam, Netherlands	en
heal.journalName	Solid State Ionics	en
dc.identifier.doi	10.1016/S0167-2738(99)00230-1	en
dc.identifier.isi	ISI:000083840400013	en
dc.identifier.volume	126	en
dc.identifier.issue	1	en
dc.identifier.spage	143	en
dc.identifier.epage	151	en