Enhanced Redox-Stable Sm0.5sr0.5feo3-Delta Electrode Material For Symmetric Solid Oxide Fuel Cells At Reduced Temperatures

A redox-stable perovskite oxide Sm0.5Sr0.5FeO3-delta (SSF) at reduced temperatures is investigated as a new promising electrode material for symmetric solid oxide fuel cells (SSOFCs). SSF exhibits well structural stability and catalytic activity in redox atmosphere at intermediate temperatures (<= 750 degrees C), and the electrical conductivity exhibits a semiconductor behavior both in cathode and anode atmosphere. To enhance the electrochemical performance of SSF by adding oxygen-ion conductor Gd0.1Ce0.9O2-delta (GDC), the electrode polarization resistances at 750 degrees C are reduced from 2.86 to 0.67 Omega cm(2) in air and from 4.32 to 0.91 Omega cm(2) in humidified H-2, respectively. Accordingly, the cell performance of SSOFCs with SSF-GDC composite electrode is almost twice (201.74 mW cm(-2 )at 750 degrees C) of those with the single-phase one. There preliminary experimental results demonstrate SSF-based electrode materials can be new promising candidates for SSOFCs at low temperatures.