Synthesis and characterization of ZnO/CuInS2 nanocomposite and investigation of their photocatalytic properties under visible light irradiation

In this work, CuInS2 (CIS) nanoparticles were synthesized via a simple and efficient reflux route and were composite with different nanostructures of ZnO by a thermal treatment process. The particle size of 56 nm was obtained using cupper acetylacetonate (Cu(acac)2), thioacetamide (C2H5NS), indium(III) chloride tetrahydrate (InCl3·4H2O) and ethylene glycol as a solvent at the reaction time of 90 min. The product was characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and ultraviolet-visible spectroscopy (UV-vis). SEM images presented the particle morphology of the CIS sample and flower-like, narcis and particle morphologies for the ZnO samples in the arranged reaction conditions. The band gap energy of 1.55 eV estimated by the diffuse reflectance spectroscopy (DRS) for CIS nanoparticles, exhibited that this product can be appropriate for photocatalytic activity in the visible region of solar spectrum. Photocatalytic activity of ZnO/CIS nanocomposite was determined by photodegradation of crystal violet under visible light irradiation. Results showed that the presence of the CIS nanoparticles improves the efficiency of the photocatalytic activity of ZnO and the removal efficiency up to 100%, which prove capability of CIS nanoparticles to depredate crystal violet from aqueous solution. In this paper, the effects of morphology of ZnO nanostructures and initial pH of solution on the photocatalytic activity are investigated.