Boosting benzene combustion by engineering oxygen vacancy-mediated Ag/CeO2-Co3O4 catalyst via interfacial electron transfer.

Oxygen vacancy (Ov) engineering is a widely accepted effective strategy to manipulate the catalytic activity for volatile organic compounds (VOCs) abatement. Herein, we report the oxygen vacancy-mediated Ag/CeO2-Co3O4 catalyst to boost benzene combustion. The incorporation of Ag species in Ag/CeO2-Co3O4 induces the predominately exposed surface Co3+ sites and structural distortion of Co3O4 as well as rich oxygen vacancy owing to the improved interfacial electron transfer, which promote the adsorption of benzene and the dissociation of oxygen. The low-temperature reducibility and mobility of oxygen species are also improved due to the generation of oxygen vacancy. The isotopic 18O2 exchange experiments demonstrate that abundant oxygen vacancies contribute to the rapid generation of active oxygen species, and the consumed oxygen vacancies can be compensated steadily during benzene oxidation. In-situ DRIFTS results reveal that benzene oxidation is a continuous oxidation process, and active oxygen species plays a crucial role in the deep oxidation of benzene by engineering oxygen vacancy. This work provides an efficient strategy for designing high-performance environmental catalysts for VOCs abatement.