A low-temperature and one-step method for fabricating ZnIn2S4–GR nanocomposites with enhanced visible light photoactivity†
ZnIn2S4–graphene (GR) nanocomposites have been fabricated by a low-temperature and one-step wet chemistry process, during which the formation of ZnIn2S4 nanosheets, the reduction of graphene oxide (GO) and intimate interfacial contact between them were achieved simultaneously. The as-prepared ZnIn2S4–GR exhibited remarkably enhanced visible light photocatalytic performance toward selective reduction of nitroaromatics to amines in water compared to blank ZnIn2S4. Controlled experiments have been carried out and revealed that an inert atmosphere and the addition of a hole scavenger are two important conditions for photocatalytic selective reduction of nitroaromatics over ZnIn2S4–GR. In comparison with blank ZnIn2S4, the remarkably enhanced photocatalytic performance of ZnIn2S4–GR can be mainly attributed to the integrative effect of the unique physicochemical properties of GR and the intimate interfacial contact between ZnIn2S4 and GR. Specifically, the introduction of GR into the matrix of ZnIn2S4 can significantly influence the morphology and structure of the samples owing to the “structure-directing” role of GO, enhance the adsorptivity of the substrate, and effectively promote the separation and transfer of photogenerated charge carriers, thereby contributing to the photoactivity enhancement. It is hoped that the current work on the facile synthesis of ZnIn2S4–GR nanocomposites can broaden the applications of ZnIn2S4–GR and other GR-based nanocomposites as visible-light-driven photocatalysts toward selective organic transformations under mild conditions.