Performance of Ba0.5Sr0.5Co0.8Fe0.2O3−δ-CGO-Ag cathode for IT-SOFCs

Single phase Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSCF) was synthesized successfully at 1000 °C by solid reaction method. The dependence of thermal expansion and electrical conductivity on temperatures were studied. Electrochemical properties of pure BSCF cathode and BSCF + CGO (20 mol% Gd2O3-doped CeO2) composite cathode on CGO electrolyte at intermediate temperatures were investigated by using AC impedance analyzer. Additionally, a composite cathode of BSCF containing 30 wt.% CGO and a small quantity of Ag was prepared and studied, which shows the lowest area specific resistance (<0.1 Ω cm2 at temperatures higher than 700 °C), being a high potential candidate of cathode for intermediate temperature SOFCs (IT-SOFCs, working at 800 °C or lower temperatures).