Synthesis and characterizations of BiVO4 based photocatalytic nano-composite

Abstract

This report attempts to find out the photocatalytic properties of BiVO4 and its modified systems. In this project the Preparation of Scheelite Monoclinic Bismuth Vanadate (BiVO4) in the form of powder as well as thin film was successfully synthesized by high energy ball milling and sol-gel spin coating method respectively.

In BiVO4 powder, modification to its system was done by transition metal doping of Molybdenum (Mo) and formation of p-n heterojunction by including copper oxide (CuO). Their properties were characterized using mainly Raman Spectroscopy, Diffuse Reflectance Spectrometer (DRS), Photoluminescence (PL) measurement and X-Ray Diffraction (XRD). Degradation of Rhodamine B (RhB) Dye under white LED light irradiation was studied for Photocatalytic Oxidation (PCO) Study. For CuO/BiVO4 composites, Surface Photovoltage (SPV) response and Photoelectrochemical (PEC) response is observed using a customized Kelvin Probe and Photoelectrochemical workbench respectively. This is due to the better photocatalytic response to the improved BiVO4 system compared to Mo-doped BiVO4 which did not show promising photocatalytic response.

In BiVO4 thin film, prepared sol-gel were spin coated onto Fluorine Doped Tin Oxide (FTO) glass before calcination at different temperature from 350°C to 500°C. It was then characterized using the XRD, Diffuse Transmission Spectroscopy (DTS), Raman Spectroscopy and PL. Similarly, PCO, SPV and PEC were also studied. In the experiment, BiVO4 thin film showed optimal photocatalytic response when calcinated at 450°C.