Mechanistic Origin of Enhanced CO Catalytic Oxidation over Co3O4/LaCoO3 at Lower Temperature

Abstract CO catalytic oxidation on the perovskite oxide LaCoO3, which can be ascribed to a decoration of Co3O4 nanoparticles on the surface, was achieved with 90 % conversion rate at 202 °C. The obtained dual‐phase catalyst was successfully synthesized through a non‐stoichiometric Ce‐induced exsolution‐like process, after an electrospinning treatment with subsequent annealing. The enhanced activity originates from the surface oxygen of LaCoO3/Co3O4 and Co3+ in the Co3O4 nanoparticles, as confirmed by X‐ray photoelectron spectroscopy (XPS) and X‐ray absorption near‐edge structure analysis (XANES). The synergic effect of the surfaced Co3O4 and parent LaCoO3 may open a path to unlocking the activity of perovskite oxides for enhanced low‐temperature CO oxidation.