A novel composite (BiVO4/TiS2) presenting an excellent Z-scheme photocatalytic degradation for Rhodamine B dye under the visible light irradiation

Abstract

Dye pollutant in the water is the most challenging problem in the textile industries. Novel composites photo-catalysts (BiVO4/TiS2@3%, BiVO4/TiS2@6%, and BiVO4/TiS2@9%) have been prepared to solve this problem. These composites proved promising materials as they have high photocatalytic performance and excellent electro-conductivity properties. Novel BiVO4/TiS2@3%, BiVO4/TiS2@6%, and BiVO4/TiS2@9% composites nanomaterials characterized by Photoluminescence Spectroscopy, UV–visible Diffuse Reflectance Spectroscopy (DRS), Raman Spectroscopy, Energy dispersive X-ray Spectroscopy, Scanning Electron Microscopy, Transmission Electron Microscopy, Fourier Transform Infrared Spectroscopy (FTIR), and X-ray Diffraction Techniques. BiVO4/TiS2@6% shows superior photocatalytic activity and removed RhB molecules (97%) in a very short time of 70 min when irradiated underneath visible light. Compared to pure BiVO4 and TiS2, the average photocatalytic efficiency of composite materials (BiVO4/TiS2@3%, BiVO4/TiS2@6%, and BiVO4/TiS2@9%) was high. Photo generated carrier's transmission becomes smooth due to the very small resistance of BiVO4/TiS2@3%, BiVO4/TiS2@6%, and BiVO4/TiS2@9%. The photoluminescence spectrum (PL) shows that photo-generated carriers of BiVO4/TiS2@6% have the highest separation efficiency. Focusing on a capturing experiment for the degradation of RhB, a good photocatalytic process was presented. It was unexpected to see how quickly the rate of degradation of a new BiVO4/TiS2@6% composite photocatalytic material could still be up to 90% after six cycles. Finally, proposed an excellent photo-catalyst BiVO4/TiS2@6% for wastewater treatment on an industrial scale.