Electrical and electrochemical characterization of microstructured thin film La1−xSrxCoO3 electrodes

Thin film microstructured La1−xSrxCoO3 (LSCO) electrodes for micro-SOFC application and kinetic studies were characterized by 4 probe electrical conductivity and electrochemical impedance spectroscopy (EIS). The electrical conductivity was analyzed between RT and 700 °C and was found to be strongly dependent on the thin film deposition parameters, in particular on the oxygen partial pressure during deposition. The highest conductivity measured at 600 °C was 700 S/cm. EIS was carried out on different substrate materials. SiO2 was found to be the most promising substrate material with respect to chemical and electrical inertness. Four main contributions were observed by EIS and were attributed respectively to the series resistance of the LSCO, to the grain boundary impedance of the CGO electrolyte and to LSCO electrode reactions.