Synthesis and characterization of Sr2Ce0.98Na0.02O4

The powder of layered perovskite oxide Sr2Ce0.98Na0.02O4 has been synthesized by conventional solid-state ceramic route by calcination at 1000 °C. Rietveld refinement of XRD data of sintered powder confirmed orthorhombic structure and space group Pbam. Further, purity and phase formation of the powder were rechecked using Raman spectroscopy technique. Spectroscopic impedance analysis has been used to study the relaxation mechanism. Two-probes DC conductivity measurement in the temperature range 200-600 °C was carried out to understand the conduction mechanism. Based on the value of the activation energy for the conduction and relaxation mechanisms, it is proposed that the origin of both the mechanism is same, that is the migration of doubly ionized oxygen vacancy (Vo..).