Photoelectrocatalytic performance improvement of BiVO4 thin film fabrication via effecting of calcination temperature strategy

The fabrication of bismuth vanadate (BiVO4) thin films on fluorine-doped tin oxide (FTO) were developed by cyclic voltammetry deposition. The effect of calcination temperature on BiVO4 thin film characteristics was studied to improve the photoelectrocatalytic water oxidation and organic dye degradation performance. A UV–visible spectrophotometer, scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and electrochemical impedance spectroscopy were used to characterize the fabricated BiVO4 thin film on the FTO substrate. The photoelectrocatalytic properties of the FTO/BiVO4 electrode were investigated by studying the efficiency of water oxidation and rhodamine B degradation. The BiVO4 thin film shows high visible light absorption and high crystallinity monoclinic BiVO4 at a calcination temperature ranging from 400 to 500 °C. The calcination temperature at 500 °C exhibits the highest photoelectrocatalytic oxidation properties related to high porosity and lowest charge transfer resistance properties. The BiVO4 thin films annealed at 500 °C, which also shows the highest rhodamine B degradation performance up to 93% for 1 h. The research confirms that calcination temperature is a significant parameter to control BiVO4 thin film characteristics and photoelectrocatalytic properties. The fabricated BiVO4 thin film at the optimum condition can apply as a photoanode for other photoelectrocatalytic applications.