Quaternary perovskite cathodes (Ca, Ce) MO₃ (M = Fe, Mn, Ni): high performance low-temperature solid oxide fuel cells

Low-temperature solid oxide fuel cells (LT-SOFCs) have attracted increasing attention as next-generation energy conversion devices due to their reduced operating costs and enhanced durability. A major challenge in this field is the development of cathode materials capable of delivering high electrochemical activity at reduced temperatures. In this study, cerium-based quaternary perovskite oxides with the general formula Ca₀.₅Ce₀.₅MO₃ (M = Fe, Mn, and Ni) were successfully synthesized via a co-precipitation route and systematically evaluated as cathodes for LT-SOFC applications. Structural integrity and phase formation were confirmed by X-ray diffraction, while Raman and UV–Vis spectroscopy provided insight into lattice vibrations and electronic structure. Surface morphology, elemental distribution, and defect chemistry including oxygen vacancy concentration—were investigated using SEM and XPS analyses. Among the compositions studied, Ca₀.₅Ce₀.₅MnO₃ (CCMO) exhibited superior electrochemical performance, delivering an open-circuit voltage of 1.03 V and a peak power density of 874 mW cm −2 at 550 °C. Impedance and current–voltage measurements further revealed enhanced charge transport characteristics for CCMO, indicating favorable electrode kinetics. These findings highlight the strong potential of CCMO quaternary perovskite nanomaterials as efficient cathodes for high-performance LT-SOFCs.