Effect of ionic conductivity of zirconia electrolytes on the polarization behavior of various cathodes in solid oxide fuel cells

Journal Article · Fri Jan 01 04:00:00 EST 1999 · Journal of the Electrochemical Society

DOI:https://doi.org/10.1149/1.1391555· OSTI ID:321123

Uchida, Hiroyuki; Yoshida, Manabu; Watanabe, Masahiro ^[1]

---

1. Yamanashi Univ., Kofu (Japan). Lab. of Electrochemical Energy Conversion

The polarization behaviors of porous platinum and La(Sr)MnO{sub 3} (LSM) cathodes coupled with zirconia electrolytes with various ionic conductivities ({sigma}{sub ion}) were investigated. The exchange current density, j{sub 0}, on Pt cathode was not influenced by the {sigma}{sub ion} at 900 and 1,000 C, whereas j{sub 0} increased proportionally to {sigma}{sub ion} at a lower temperature of 800 C. However, the j{sub 0} on LSM cathodes increased in proportion to the {sigma}{sub ion} in the temperature region between 800 and 1,000 C. The dispersion of nanometer-sized Pt catalysts on LSM particles greatly enhanced the performance, the magnitude of which depended on the temperature, the {sigma}{sub ion}, and the microstructure of LSM. The observations are well explained kinetically, i.e., the cathode performance is controlled by the transport rate of O{sup 2{minus}} at the interface when the surface reaction rate is sufficiently high. Consequently, the use of high-performance electrodes in combination with the solid electrolyte having high {sigma}{sub ion} is very important for achieving the high performance of solid oxide fuel cells.

• OSTI ID: 321123
• Journal Information: Journal of the Electrochemical Society, Journal Name: Journal of the Electrochemical Society Journal Issue: 1 Vol. 146; ISSN 0013-4651; ISSN JESOAN
• Country of Publication: United States
• Language: English

Related Subjects

30 DIRECT ENERGY CONVERSION
36 MATERIALS SCIENCE
CATHODES
IONIC CONDUCTIVITY
LANTHANUM OXIDES
MANGANESE OXIDES
PERFORMANCE
PLATINUM
SOLID ELECTROLYTE FUEL CELLS
STRONTIUM OXIDES
ZIRCONIUM OXIDES