Thermal and Electrical properties of Ce0.8−x Gd x Sm0.2O2−δ materials for SOFC applications

Abstract

Gadolinium and samarium co-doped ceria electrolyte materials Ce0.8−x Gd x Sm0.2O2−δ (x = 0, 0.02, 0.04, 0.06) were prepared by using sol–gel method. The prepared materials were characterized by X-ray diffraction and scanning electron microscopy. The phase identification and the cell parameters were determined by X-ray powder diffraction. Thermal expansion of prepared materials was measured using dilatometric method in the temperature range 30–1000 °C. The thermal expansion increases linearly increasing temperature. The electrical conductivity was measured using impedance spectroscopy. Among the prepared compositions, Ce0.74Gd0.06Sm0.2O2−δ showed higher electrical conductivity and lower activation energy at 450 °C. Which makes suitable as an electrolyte and it may be a promising candidate for as an electrolyte in IT-SOFCs.