Enhancing photocatalytic H2O2 production and green oxidation of glycerol with OV-Bi2O2S/CuCo2O4 through electronic structure modification

Hydrogen peroxide (H2O2) production is limited due to the inherent presence of photocatalysts with low carrier utilization and slow reaction kinetics. In this study, the photocatalytic system supported by Ov-Bi2O2S/CuCo2O4 (Ov-BOS/CCO) heterojunctions was successfully synthesized to enhance the adsorption of O2 at Co sites and increase the H2O2 production by altering the electronic structure to form electron-deficient Co delta+ sites. By using glycerol (GLY) as the sacrificial agent, the Ov-BOS/CCO catalysts were able to significantly enhance the rate of H2O2 generation to 32.33 mmol center dot g- 1 center dot h- 1. The Ov-BOS caused the creation of electron-deficient Co delta+ sites, which adjusted the orbital occupancy of Co-Oads and hence regulated the adsorption of O2 according to densityfunctional theory calculations (DFT). Furthermore, as a special proton donor, GLY effectively trapped holes (h+) to increase the generation of H2O2 and produced the valuable by-product oxalic acid (OA). This strategy may contribute to the rational design of the electronic structure of the photocatalyst surface.