Abstract
Crystal structure, thermal expansion, oxygen stoichiometry, thermoelectricity, and electrical conductivity of compositions in the system La1 - xSrxCo0.2Fe0.8O3 with 0 ≤ x ≤ 0.6 were studied as function of temperature and Sr content, in air. The solubility of Sr in the sintered perovskite-type oxide (ABO3) was limited to x ≤ 0.4. The observed p-type electrical conduction appeared to occur via a small-polaron hopping mechanism. The thermally induced oxygen loss caused a lattice expansion plus decreases in both the carrier concentration and the carrier mobility. A semi-empirical model was developed which takes into account the thermally activated disproportionation of Co3+ ions into Co4+ and Co2+ pairs, and the ionic compensation of oxygen vacancies formed at high temperatures. The concentrations of B-site ions (Co or Fe) in different valence states were calculated using this model and experimental data. © 1995.
Recommended Citation
L. W. Tai et al., "Structure and Electrical Properties of La1 - XSrxCo1 - YFeyO3. Part 2. the System La1 - XSrxCo0.2Fe0.8O3," Solid State Ionics, vol. 76, no. 3 thru 4, pp. 273 - 283, Elsevier, Jan 1995.
The definitive version is available at https://doi.org/10.1016/0167-2738(94)00245-N
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
