(BaxSr1-x)(CoyFe1-y)O3-δ Perovskites as SOFC Cathode Material: Electrode-Electrolyte Reactions and Electrochemical Characterisation

Abstract

(BaxSr1-x)(CoyFe1-y)O3-d (BSCF) perovskites are promising SOFC cathode materials. The interfacial reaction with zirconia and ceria electrolyte materials is investigated. The electrochemical performance is studied for y = 0.8, x = 0.25 and 0.5, using im-pedance spectroscopy on dense thin-film microelectrodes, which allows one in particular to determine absolute values of the surface resistance unaffected by morphology effects. Temperature, oxygen partial pressure and applied DC bias are varied to obtain a broad data basis for a further mechanistic analysis.