Electrochemical performance of BaZr0.1Ce0.7Y0.1Yb0.1O3−δ electrolyte based proton-conducting SOFC solid oxide fuel cell with layered perovskite PrBaCo2O5+δ cathode

▶ BaZr0.1Ce0.7Y0.1Yb0.1O3−δ (BZCYYb) as electrolyte exhibits high conductivity as well as sufficient chemical stability over a wide range of SOFC practical operating conditions, while layered perovskite PrBaCo2O5+δ (PBCO) has advanced oxygen reduction ability. This research fully takes advantage of these advanced properties and develops a novel protonic ceramic membrane fuel cell (PCMFC) of Ni-BZCYYb|BZCYYb|PBCO. The results show that the maximal power density of 490 mW cm−2 and the electrode polarization resistance of 0.11 Ω cm2 were achieved at 700 °C. ▶ The polarization processes of the button cell were characterized using the complicated electrochemical impedance spectroscopy (EIS) technique. The results indicate that the polarization resistances contributed from both charge migration processes and mass transfer processes increase with decreasing cell voltage loads. However the polarization resistance induced by mass transfer processes is negligible in the studied button cell. ▶ By co-doping barium zirconate-cerate with Y and Yb, the conductivity of electrolyte was significantly improved.