A COMPARATIVE STUDY OF 20 MOLE % Gd 2 O 3 DOPED CeO 2 PREPARED BY DIFFERENT SYNTHETIC ROUTES

A b s t r a c t In recent years, a growing interest in properties of nanostructured ion conductors, has been observed. Solid electrolytes for Solid Oxide Fuel cell (SOFC) should be highly dense material due to gas-tight requirement. It is noted that the sintering and densification behavior of ceria-based electrolytes rely on synthetic route and temperature of calcinations. Hence, gadolinium doped ceria samples were prepared, by the cation complexation technique which is a variant of sol-gel technique, using citric acid as complexing agent and also by ceramic route. X-ray diffraction (XRD) and simultaneous TG/DTA technique were used, to characterize the samples. The purpose of this work was to prepare the powders with 10-20 nm of crystallite size at a relatively low temperature. A comparative study of their particle size, densification, thermal expansion and ionic conductivity was carried out.