Novel cobalt-free cathode materials BaCexFe1−xO3−δ for proton-conducting solid oxide fuel cells

A series of cobalt-free and low cost BaCexFe1−xO3−δ (x = 0.15, 0.50, 0.85) materials are successful synthesized and used as the cathode materials for proton-conducting solid oxide fuel cells (SOFCs). The single cell, consisting of a BaZr0.1Ce0.7Y0.2O3−δ (BZCY7)-NiO anode substrate, a BZCY7 anode functional layer, a BZCY7 electrolyte membrane and a BaCexFe1−xO3−δ cathode layer, is assembled and tested from 600 to 700 °C with humidified hydrogen (∼3% H2O) as the fuel and the static air as the oxidant. Within all the cathode materials above, the cathode BaCe0.5Fe0.5O3−δ shows the highest cell performance which could obtain an open-circuit potential of 0.99 V and a maximum power density of 395 mW cm−2 at 700 °C. The results indicate that the Fe-doped barium cerates can be promising cathodes for proton-conducting SOFCs.