FeO Octahedral Distortion Activates Lattice Oxygen in Perovskite Ferrite for Methane Partial Oxidation Coupled with CO Splitting.

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 FeO octahedra in LaCeFeO ( = 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 FeO octahedral distortion in LaCeFeO promoting their bulk oxygen mobility and surface oxygen exchange capability. Consequently, LaCeFeO with the highest FeO distortion achieves exceptional syngas productivity of ∼3 and 8 times higher than LaFeO and CeFeO, respectively, in CH partial oxidation step with simultaneous high CO conversion (92%) in the CO-splitting step at 850 °C. The results exemplify the feasibility to tailor the active lattice oxygen of perovskite by modulating the distortion of BO in ABO, which ultimately influences their reaction performance in chemical looping processes.