Novel layered perovskite SmBaCu2O5+δ as a potential cathode for intermediate temperature solid oxide fuel cells

A novel layered perovskite SmBaCu2O5+δ (SBCO) as a potential cathode for intermediate temperature solid oxide fuel cells (IT-SOFC) has been investigated in this paper. The SmBaCu2O5+δ oxide was synthesized by EDTA- Citrate complexing sol-gel process. The crystal structure, the thermal expansion, the electrical conductivity and electrochemical properties have been characterized by X-ray diffraction (XRD), dilatometer, four-probe dc method, electrochemical impedance spectroscopy (EIS) and cathodic polarization examinations. The average thermal expansion coefficient (TEC) of SBCO was 14.6 × 10−6/ °C in the temperature range of 50–800 °C, which matched Sm-doped ceria (SDC) electrolytes. The electrode polarization resistance was 0.469 Ωcm2. Considering low thermal expansions and good electrochemical properties, layered perovskite SBCO shows promising performance as cathode material for IT-SOFCs.