Biomolecule-assisted solvothermal synthesis of Cu2SnS3 flowers/RGO nanocomposites and their visible-light-driven photocatalytic activities

Abstract

Elimination of organic pollutants from wastewaters under visible-light irradiation is a venerable challenge in the fields of environmental and material science. In this work, we present a facile eco-friendly method to fabricate novel Cu₂SnS₃ flowers/RGO (Cu₂SnS₃/RGO) nanocomposites via a solvothermal method using L-cysteine as a sulphur source and linker. The crystal structure, morphology, purity, spectroscopic, and charge carrier separation properties of the synthesized samples were studied by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission-scanning electron microscopy (FE-SEM), high resolution transmission electron microscopy (HR-TEM), and X-ray energy-dispersive spectroscopy (EDS), Raman spectroscopy, UV-vis diffuse reflectance spectroscopy (UV-vis DRS) and electrochemical impedance spectroscopy (EIS). The photocatalytic performance of the Cu₂SnS₃/RGO nanocomposites was evaluated by photocatalytic decolorization of eosin under visible-light irradiation. Results showed that the Cu₂SnS₃/RGO (3%) nanocomposite exhibits enhanced photocatalytic activity compared with the pure Cu₂SnS₃. The improved photocatalytic activity of the nanocomposite was mainly attributed to the formation of well-defined interface between Cu₂SnS₃ and graphene sheets, which greatly enhance the charge carrier separation efficiency in the Cu₂SnS₃ semiconductor.