Influence of anode pore forming additives on the densification of supported BaCe0.7Ta0.1Y0.2O3−δ electrolyte membranes based on a solid state reaction

We describe a solid state reaction for the preparation of both NiO–BaCe0.7Ta0.1Y0.2O3−δ anode substrates and BaCe0.7Ta0.1Y0.2O3−δ (BCTY10) electrolyte membranes on porous NiO–BCTY10 anode substrates. The amounts of the pore forming additive in the substrates showed a significant influence on the densification of the BCTY10 membranes. After sintering at 1450 °C for 5 h, the BCTY10 membrane on a NiO–BCTY10 anode containing 30 wt.% starch achieved a high density and showed adequate chemical stability against H2O and CO2. The chemical stability of BCTY10 was even better than that of BaCe0.7Zr0.1Y0.2O3−δ. With a mixture of BaCe0.7Zr0.1Y0.2O3−δ (BZCY7) and La0.7Sr0.3FeO3−δ (LSF) as a cathode, a single fuel cell with 12 μm thick BCTY10 electrolyte generated maximum power densities of 142, 93, 29 mW/cm2 at 700, 600 and 500 °C, respectively. The electrolyte resistance and interfacial polarization resistance of the cell under open circuit conditions were also investigated.