Geometry dependence of cathode polarization in solid oxide fuel cells investigated by defined Sr-doped LaMnO3 microelectrodes

Authors
Brichzin, V Fleig, J Habermeier, HU Maier, J
Citation
V. Brichzin et al., Geometry dependence of cathode polarization in solid oxide fuel cells investigated by defined Sr-doped LaMnO3 microelectrodes, EL SOLID ST, 3(9), 2000, pp. 403-406
Citations number
27
Categorie Soggetti
Physical Chemistry/Chemical Physics
Journal title
ELECTROCHEMICAL AND SOLID STATE LETTERS
ISSN journal
10990062 → ACNP
Volume
3
Issue
9
Year of publication
2000
Pages
403 - 406
Database
ISI
SICI code
1099-0062(200009)3:9<403:GDOCPI>2.0.ZU;2-A
Abstract
Microcontact impedance spectroscopy was used to measure the electrode polar ization resistance of geometrically defined, thin, circular (La0.8Sr0.2)(0. 92)MnO3 (LSM) microelectrodes deposited on yttria-stabilized zirconia (YSZ) as a function of the electrode diameter (similar to 20-200 mu m). The elec trode polarization resistance is proportional to the inverse of the square of the electrode diameter. This clear result indicates a rate-determining s tep of the oxygen reduction that is connected with the electrode area rathe r than depending on the length of the three-phase boundary LSM, O-2/YSZ. (C ) 2000 The Electrochemical Society. S1099-0062(00)05-062-8. All rights rese rved.