Pervoskite-type BaCo0.7Fe0.2Ta0.1O3−δ cathode for proton conducting IT-SOFC

This paper presents Pervoskite-type BaCo0.7Ta0.1Fe0.2O3−δ (BCTF) cathode for intermediate temperature proton conducting solid oxide fuel cells (SOFCs). BCTF with cubic phase shows excellent structural stability and adequate chemical stability against CO2/H2O in contrast to BaCo0.8Fe0.2O3−δ. Conductivity of BCTF reaches above 10 S cm−1 in air at intermediate temperatures. Composite cathode polarization resistance (BCTF/BaZr0.1Ce0.7Y0.2O3−δ) in a symmetric cell based on proton conducting BaZr0.1Ce0.7Y0.2O3−δ (BCZY) electrolyte was as low as 0.1 Ω cm2 at 700 °C. The maximum output of anode-supported thin-film SOFC with BCTF/BCZY composite cathode and BCZY electrolyte reaches 255 mW cm−2 when employing humidified H2 as fuel and static air as oxidizer.