Hybridization of CuO with BiVO4 as an Efficient and Stable Photocatalyst for Selective Cleavage of Lignin C–C Bonds

Abstract

The solar-driven transformation of lignin into aromatic compounds is a promising approach for biomass utilization. However, selective cleavage of lignin C–C bonds on the solid catalyst surface under suitable conditions is a difficult task. Here, a CuO/BiVO₄ hybrid was reported for the selective oxidation of C–C bonds under simulated sunlight at room temperature. The synergistic effect of CuO and BiVO₄ benefited charge dynamics and transfer from the photoexcitation sites to the active centers. The model substrate representing lignin β-O-4 linkages was converted into aromatic compounds with 86.5% C–C cleavage selectivity, and the aromatic compounds were produced with a yield reaching 665.03 μmol g_cat^–1·h^–1. Mechanistic studies showed that C_α–C_β bonds were efficiently cleaved mainly through hydrogen abstraction from the β-carbon by photogenerated holes and the generation of ^?O₂^– from adsorbed O₂ by photoexcited electrons. The result provided new views into the development of more efficient photocatalysts for the cleavage of lignin C–C bonds through interfacial engineering.