Polycrystalline BaCeO3 and BaCe0.7Zr0.3O3 were prepared by using the citrate-EDTA complexing sol-gel process at low temperature (T=1000 ?C). The pure phase formation with temperature was studied by x-ray diffraction (XRD) and thermal analysis (TG-DTA). The crystallite size of the ceramic powders was calculated from Scherrer's equation. A slight decrease in the crystallite size was found when Zr was doped and the diffraction peak shifted to higher angles. Morphology of the powders sintered at T=1300 oC exhibited a slight decrease in the average grain size from 1.33 μm to 1.25 μm. This is consistent with the fact that the grain size decreased as the ionic radius of Zr is less than Ce. Dense ceramic materials were obtained at T=1300 oC and the relative density were found to be 79% of the theoretical density. FTIR and Raman measurements revealed the complete single phase formation of the perovskite. The ionic conductivities of both the compounds were investigated from 30-400oC and are found to be 1.92x10-6Scm-1 and 1.35x10-6S cm-1 at 400oC respectively. The conductivity decreases as temperature increases and the activation energies are 1.21 eV and 1.34 eV respectively. These values are in agreement with that available in the literature.
BaCeO3, Citrate-EDTA complexing sol-gel process, Perovskite, Fuel cells, Protonic conductor