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

Sr2Fe1.5Mo0.5O6- (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 BaZro.iCeo.7Y0.203-6 (BZCY) electrolyte. SFM is synthesized with a combined glycine and citric acid method and shows very good chemical compatibility with BZCY under 1100 C. Anodesupported 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 0 cm2 is achieved at 800 C when cathode is sintered at 900 C for 2 h. The single fuel cell achieves 396 mW cm-2 at 800 C in wet H2 (3 vol% H20) 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. (C) 2014 Elsevier B.V. All rights reserved.