Abstract
Crystal structure, thermal expansion, thermogravimetry, thermoelectricity, and electrical conductivity of compositions in the system La0.8Sr0.2Co1-yFeyO3 with 0 ≤ y ≤ 1 were studied as function of Co Fe ratio and temperature, in air. The electrical conduction mechanism is attributed to the adiabatic-hopping of p-type small polarons. At high temperatures, oxygen deficiency causes lattice expansion and a reduction in electrical conductivity. The observed temperature dependence of the Seebeck coefficient is attributed to changes in carrier concentration caused by a thermally excited charge disproportionation of Co3+ ions and by the ionic compensation of induced oxygen vacancies. The measured electrical conductivity and Seebeck coefficient as a function of the Co Fe ratio is interpreted using a two-site hopping and the site-percolation model. It is suggested that a preferential electronic compensation of Fe ions over Co ions may occur in this system. © 1995.
Recommended Citation
L. W. Tai et al., "Structure and Electrical Properties of La1-XSrxCo1-YFeyO3. Part 1. the System La0.8Sr0.2Co1-YFeyO3," Solid State Ionics, vol. 76, no. 3 thru 4, pp. 259 - 271, Elsevier, Jan 1995.
The definitive version is available at https://doi.org/10.1016/0167-2738(94)00244-M
Department(s)
Materials Science and Engineering
Second Department
Physics
Keywords and Phrases
LSCF compositions; Mixed-conducting oxides; Perovskite; Small-polaron conductor; Solid oxide fuel cell (SOFC)
International Standard Serial Number (ISSN)
0167-2738
Document Type
Article - Journal
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 2024 Elsevier, All rights reserved.
Publication Date
01 Jan 1995
