Proton conducting intermediate-temperature solid oxide fuel cells using new perovskite type cathodes

Sr2Fe1.5Mo0.5O6-δ(SFM) is proposed as the electrodes for symmetric solid oxide fuel cells (SOFCs) based on oxygen-ion conducting electrolytes. In this work SFM is investigated as the cathodes for SOFCs with proton conducting BaZr0.1Ce0.7Y0.2O3-δ(BZCY) electrolyte. SFM is synthesized with a combined glycine and citric acid method and shows very good chemical compatibility with BZCY under 1100 °C. Anode-supported single cell (Ni-BZCY anode, BZCY electrolyte, and SFM-BZCY cathode) and symmetrical fuel cell (SFM-BZCY electrodes and BZCY electrolyte) are fabricated and their performances are measured. Impedance spectroscopy on symmetrical cell consisting of BZCY electrolyte and SFM-BZCY electrodes demonstrates low area-specific interfacial polarization resistance Rp, and the lowest Rp, 0.088 Ω cm2is achieved at 800 °C when cathode is sintered at 900 °C for 2 h. The single fuel cell achieves 396 mW cm-2at 800 °C in wet H2(3 vol% H2O) at a co-sintering temperature of 1000 °C. This study demonstrates the potential of SFM-BZCY as a cathode material in proton-conducting intermediate-temperature solid oxide fuel cells.