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• Low temperature CO 2 to CO conversion by perovskite oxide materials La 1-x Ba x FeO 3. • Stabilized perovskite catalyst structure during redox reaction. • La 0.4 Ba 0.6 FeO 3 is the optimal composition for balancing CO yield and catalyst stability. • Surface reaction modeled as adsorbed CO 2 γ− dissociated to CO and O. Reverse water-gas shift chemical looping (RWGS-CL) is a low temperature thermochemical process to convert CO 2 to CO by perovskite oxides. In this research, perovskite oxides of the form of La 1- x Ba x FeO 3 (x = 0.25−0.75) are explored for enhancing CO yield while maintaining stability over multiple cycles. DFT was utilized to calculate the oxygen vacancy formation energies (E vac) identifying E vac of La 0.75 Ba 0.25 FeO 3 (3.3 eV) and La 0.5 Ba 0.5 FeO 3 (3.0 eV) are in the ideal range of 3.4 ± 0.5 eV. Additional Ba resulted in instability. XRD confirmed cubic perovskite structure and XRF analysis established the precise composition. XPS revealed that the materials had Ba enrichment at the surface, compared to the overall bulk. Temperature-programmed reduction (TPR) and oxidation (TPO) experiments determined that CO 2 is converted to CO in the low temperature range of 400–600 °C for all compositions, which is lower than temperatures of many thermochemical CO 2 processes. Isothermal cycling between hydrogen and CO 2 at 600 °C indicated La 0.5 Ba 0.5 FeO 3 and La 0.4 Ba 0.6 FeO 3 were stable (verified by XRD and XPS) and produced CO at high yields of 200 and 500 μmol/g LBF , respectively. The CO 2 conversion step fits to Langmuir–Hinshelwood type kinetics based on its partial pressure dependency and is consistent with DRIFTS studies. Therefore, multiple materials in this study enhance performance, indicating their suitability for industrial scale adaptation upon energy integration as a possible strategy for renewable energy storage in chemical form. [ABSTRACT FROM AUTHOR]