Construction of 2D/1D ZnIn2S4/ZnO with Z-scheme system for boosting photocatalytic performance

Abstract

The construction of multidimensional composite photocatalysts with substantial photocatalytic performance, fast charge separation, and a wide light absorption range system poses a major challenge to the field of photocatalytic research. Here, ZnO nanorods with assembling ZnIn2S4 nanosheets via a hydrothermal approach to construct a unique Z-scheme 2D/1D ZnIn2S4/ZnO heterojunction photocatalyst. The morphology, composition, microstructure, and properties of the 2D/1D ZnIn2S4/ZnO photocatalyst were thoroughly investigated through a variety of detailed characterizations. Scanning electron microscopy (SEM) and transmission electron microscope (TEM) findings showed that a significant number of ZnIn2S4 nanosheets evenly grew on the surface of ZnO nanorods. Based on the XPS investigation, the close chemical interaction between ZnIn2S4 and ZnO was identified. The visible light absorption range of the as-prepared photocatalysts was expanded, facilitating electron–hole separation upon photoexcitation according to UV–vis DRS and electrochemical tests. Under light radiation, the 2D/1D ZnIn2S4/ZnO photocatalyst can degrade 96.84 % of methyl orange (MO) within 120 min. Furthermore, the photocatalytic hydrogen evolution rate reached 3348.3 μmol/g/h within 6 h. The enhanced photocatalytic performance was substantial because of the Z-scheme system formed between ZnIn2S4 and ZnO and the 2D/1D nanostructures’ nature, which facilitated carrier transfer and increased the number of active sites for photocatalytic reactions. The charge transfer mechanism of ZnIn2S4/ZnO was discussed in detail according to radical trapping experiments. We expect that the fabrication of 2D/1D materials with a Z-scheme system will offer new ideas and record the development of high-efficiency energy conversion photocatalysts.