FeO6Octahedral Distortion Activates Lattice Oxygen in Perovskite Ferrite for Methane Partial Oxidation Coupled with CO2Splitting

Modulating lattice oxygen in metal oxides that conducts partial oxidation of methane in balancing C–H activation and syngas selectivity remains challenging. This paper describes the discovery of distorting FeO6octahedra in La1–xCexFeO3(x= 0, 0.25 0.5, 0.75, 1) orthorhombic perovskites for the promotion of lattice oxygen activation. By combined electrical conductivity relaxation measurements and density functional theory calculations studies, this paper describes the enhancement of FeO6octahedral distortion in La1–xCexFeO3promoting their bulk oxygen mobility and surface oxygen exchange capability. Consequently, La0.5Ce0.5FeO3with the highest FeO6distortion achieves exceptional syngas productivity of ∼3 and 8 times higher than LaFeO3and CeFeO3, respectively, in CH4partial oxidation step with simultaneous high CO2conversion (92%) in the CO2-splitting step at 850 °C. The results exemplify the feasibility to tailor the active lattice oxygen of perovskite by modulating the distortion of BO6in ABO3, which ultimately influences their reaction performance in chemical looping processes.