Effects of Copper Oxide Addition on the Electrochemical Properties of Samarium Doped Ceria Electrolyte for Intermediate Temperature Solid Oxide Fuel Cells

Abstract

Low temperature sintering of samarium doped ceria (Sm0.2Ce0.8O1.9, SDC) can be required for metal-supported solid oxide fuel cells. Sintering aids (mostly transition metal oxides) can be used to substantially reduce the sintering temperature which also has an effect on the overall electrochemical process. 0-10 mol% of copper oxide and lithium oxide are added to the ceria solid solution through glycine nitrate combustion process and sintered at different temperatures ranging between 1000 and 1450°C. Hebb-Wagner polarization method and Electrochemical Impedance Spectroscopy (EIS) are used to separately characterize ionic conductivity, electronic conductivity and transference numbers. The results show that the 5% CuO/SDC sintered at 1100°C leads to similar total conductivity as pure SDC sintered at 1450°C, but the electronic conductivity decreases, which is expected to contribute to reducing the mixed ionic/electronic nature of the electrolyte.