Ionic conductors with the composition SrTi1−xCexO3 (x = 0, 0.02, and 0.04) were synthesized by a high-temperature conventional ceramic route, and their electrical properties were analyzed for use as solid electrolytes in intermediate-temperature solid oxide fuel cells (IT-SOFCs). Scanning electron microscopy/energy-dispersive x-ray spectroscopy (SEM-EDX) was used to analyze the compositional homogeneity and morphology of the samples. The phase analysis was performed using X-ray diffraction (XRD), followed by Rietveld refinement, confirming the cubic crystal structure under the space group \(Pm\overline{3 }m\) . The bands at 462 cm−1 and 449 cm−1 in the Raman spectrum confirmed the incorporation of Ce at the Ti-site of SrTiO3. The presence of a negative charge was found from zeta potential analysis, supporting the presence of Ce3+ at the Ce4+site, denoted by \(C{e}_{C{e}^{4+}}^{3+}{^\prime}\) , and Ti3+ at the Ti4+ site, denoted by \(T{i}_{T{i}^{4+}}^{3+}{^\prime}\) , in X-ray photoelectron spectroscopy (XPS) analysis. The total conductivity of samples showed thermal-dependent Arrhenius behavior with two different activation energy values. The activation energy \(\ge 1 \text{eV}\) in high-temperature regions indicated the migration of doubly ionized oxygen vacancy and \(\le 0.50 \text{eV}\) reflecting the migration of electrons between the degenerate sites of Ti4+/Ce4+. The impedance spectroscopy studies suggested the presence of bulk contribution in the electrical properties, and similar charge carriers were responsible for both processes. The impact of oxygen vacancy on electrical conduction was also supported by the magnetic properties, which displayed diamagnetic to paramagnetic phase transition with Ce doping. The highest value of total conductivity was obtained around 0.003 S cm−1 at 610°C, making it a potential candidate for solid electrolytes in IT-SOFC applications.
