A Comparison of LSM, LSF, and LSCo for Solid Oxide Electrolyzer Anodes

Abstract

Composite electrodes of yttria-stabilized zirconia (YSZ) with (LSM), (LSF), and (LSCo) were prepared and tested as solid oxide electrolyzer (SOE) anodes and solid oxide fuel cell (SOFC) cathodes at , using cells with a YSZ electrolyte and a Co-ceria-YSZ counter electrode. The LSM-YSZ electrode was activated by cathodic polarization but the enhanced performance was found to be unstable during electrolysis, with the electrode impedance increasing to near its unenhanced state after . LSF-YSZ and LSCo-YSZ electrodes exhibited a nearly constant impedance, independent of current density, during both SOE and SOFC operation. The performance of an LSF-YSZ composite for electrolysis current densities above was unaffected by changing the partial pressure from , while the lower pressure harmed the performance of the LSCo-YSZ composite. The implications of these results for the characterization and optimization of SOE anodes is discussed.