Oxygen vacancies-enriched porous CeO2-Co3O4 hybrid nanosheets for high-efficiency toluene catalytic oxidation

Catalytic oxidation is an efficient method for mitigating toluene emissions, but enhancing catalytic performance for toluene oxidation remains a challenge. To enhance the oxidation capacity of catalysts, appropriate morphology and composition adjustments are required. Herein, the porous CeO2-Co3O4 hybrid nanosheets (CeO2-Co3O4 HNSs) have been designed and prepared by the hydrothermal method. Compared with single composition CeO2 and Co3O4, the CeO2-Co3O4 HNSs exhibit superior performance, achieving a remarkable 90% toluene conversion at a reaction temperature of 215°C with a space velocity of 36,000 mL/(h·g). Their enhanced activity can be attributed to the unique morphology and multi-component synergistic effect. The introduction of Co can significantly increase the content of oxygen vacancy (Ov) and optimize the electronic structure, which can enhance the formation of surface-active oxygen and accelerate the cycle of the Ce3+/Ce4+ redox pair. This work establishes a promising avenue for treating volatile organic compounds in exhaust emissions.