Barium cerate-zirconate electrolyte powder prepared by carbonate coprecipitation for high performance protonic ceramic fuel cells

Proton-conducting perovskite oxide BaCe0.7Zr0.1Y0.2O3-delta (BZCY) is prepared by carbonate coprecipitation method using Tween-80 as the surfactant. A powder with well dispersed particles of an average size of 200 nm is obtained. The powder is applied as the original material of the electrolyte in an Ni-based anode-supported protonic ceramic fuel cell (PCFC). The electrolyte can be densified to high density after co-sintering with the anode substrate, without any sintering aids, at 1400 degrees C in open air. The PCFC with an electrolyte thickness of 20 mu m, using humid hydrogen (3% H2O) as the fuel and ambient air as the oxidant, gives a peak power density of 1050 mW cm-2 at 700 degrees C. The conducting activation energy of the electrolyte is 0.36 eV. The superiority of the BZCY powder prepared by the coprecipitation method is investigated by comparing with a BZCY powder made by conventional solid-state reaction method.