Gd 0.8 Sr 0.2 CoO 3- δ –Sm 0.1 Ce 0.9 O 1.95 composite cathode for intermediate temperature solid oxide fuel cells

Abstract Gd 0.8 Sr 0.2 CoO 3- δ –x Sm 0.1 Ce 0.9 O 1.95 (GSC- x , x = 0–50 wt.%) composite cathodes were prepared by Glycine-Nitrate Process followed by mixing GSC and SDC powder. The thermal stability and electrical conductivity of GSC- x composite cathodes have been investigated for the application in intermediate temperature solid oxide fuel cells (IT-SOFCs). The thermal expansion coefficient of GSC- x decreased with the addition of SDC. The electrical conductivities of GSC-x cathode with 0–30 wt.% SDC were passed the line of 100 S cm −1 . Especially for GSC-20, the conductivity of GSC-20 is more than 300 S cm −1 in temperature range of 600–750 °C. The area specific resistance (ASR) of GSC-20 was only 0.080 Ω cm 2 at 750 °C, much lower than that of GSC cathode (ASR = 0.119 Ω cm 2 ). The thermal expansion coefficient of GSC-20 decreased to 80% TEC of GSC cathode.