Effects of Fe2O3 addition on the electrical properties of SDC solid electrolyte ceramics

Abstract

Ceria-based electrolyte powders consisting of Fe2O3 and Sm2O3 double-doped ceria (Ce0.8Sm0.2−xFexO2−δ) were synthesized by a sol–gel method. The structure and electrochemical characters of the electrolyte materials have been studied. The phase formation of precursor powders was studied by the X-ray diffraction analysis (XRD). Microstructural and sinterability measurements were carried out on the sintered electrolyte discs. Electrochemical impedance spectroscopy (EIS) was used for estimate the electrochemical properties. The results displayed that crystalline cubic fluorite structured is formed after calcined at 700 °C. The electrochemical analysis results showed that the electrical properties of Ce0.8Sm0.2O1.9 (SDC) electrolytes substituted with certain Fe2O3 were superior and a total conductivity of 0.0263 S cm−1 could be obtained in the x = 0.1 sample. Therefore, it was concluded that co-doped with Fe2O3 and Sm2O3 could enhance the electrical conductivities of CeO2-based solid electrolyte, indicating that it is a potential electrolyte for SOFCs.