Effective Breaking of β-o-4 Bonds in Lignin Model Compounds by g-C3N4/ZnIn2S4 Photocatalyst Under Visible Light

Abstract

In this study, cauliflower-like g-C3N4/ZnIn2S4 composite photocatalysts were prepared via a hydrothermal method by loading ZnIn2S4 on g-C3N4 nanosheet layers. The crystal structures of the prepared samples were characterized by X-ray diffractometer. TEM and XPS characterization indicated the successful catalyst compounding, while PL and UV-Vis-DRs characterization illustrated the broadening of the visible light absorption interval of g-C3N4/ZnIn2S4 and the low photogenerated electron-hole complexation rate. The lignin model compounds were degraded under visible light, and the GC-MS analysis of the composition of the products showed that CN/ZIS-15 degraded, with 94% conversion of 2-phenoxy-1-phenylethanol(PP-ol) in 3 h, which was 2.5 times higher than that of pure g-C3N4, and the main products being acetophenone (AP) and phenol (Phol). The reactive radical trapping experiments were carried out to investigate the main reactive species in the reaction and to explore the mechanism for the breaking of β-O-4 bond.