Construction of CeO2/CdS Heterostructure and Study on Photocatalytic Mechanism of Rhodamine B Degradation

A series of CeO2/CdS photocatalysts were prepared by simple solvothermal and auxiliary calcination using cerium nitrate as the precursor. Two different forms of CeO2 (nanosheets (NF-CeO2) and nanorods (NR-CeO2)) were successfully prepared and used to degrade rhodamine B (RhB) to study the photocatalytic activity of the composites. On this basis, the effects of composite proportion and preparation technology on the photocatalytic activity of the composites were studied. The morphology, structure, photoelectric properties and chemical composition of the composites were analyzed. Compared with single photocatalysts (NR-CeO2 and CdS), the NF-CeO2/CdS and NR-CeO2/CdS composite catalyst have stronger photocatalytic performance. In addition, capture experiments and ESR showed that both ∙O2-\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\bullet {O}_{2}^{-}$$\end{document} and h+ impacted on the RhB degradation. After four repeated cycles, NR-CeO2/CdS (1:6) showed stable RhB degradation activity. In the aspect of catalyst interface design, this work not only provides an effective method for the preparation of catalysts with high photodegradation rate and good reuse, but also provides a feasible idea for further research on the degradation of emerging pollutants by photocatalysts.