Abstract

The stability of high-temperature fuel cell electrodes to their ambient environment is important for the long-term reliability of fuel cells. In this report the behavior of oxide electrode materials as a function of oxygen activity and temperature is considered. Models for the oxidation-reduction behavior of both p- and n-type oxides are presented. These models take into account the absorption and evolution of oxygen which take place as oxygen activity is varied. The resulting instability in electrical conductivity is explained as a consequence of changes in carrier concentration due to variability in ionic defect concentration. The proposed models are applied to acceptor-doped LaCrO3 and donor-doped SrTiO3. It is shown that the models explain the experimental data well and as a consequence diagram can be made which show the regions of oxygen activity and temperature for which stability of electrical conductivity and defect structure might be expected. © 1985.

Department(s)

Materials Science and Engineering

International Standard Serial Number (ISSN)

1095-726X; 0022-4596

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2023 Elsevier, All rights reserved.

Publication Date

01 Mar 1985

Share

 
COinS