Bismuth Vanadate Microspheres: Utilizing Temperature-driven Phase Transition for Improved Sunlight-Driven Photocatalysis and Antibacterial Efficacy

In this work, bismuth vanadate (BiVO4) microspheres are synthesized using a simple, cost effective, co-precipitation technique. This study investigates how the annealing temperature influences the photocatalytic and antimicrobial properties of nanoparticles made of BiVO4. Examining the phase structure, chemical compounds state, composition of chemicals, shape, as well as optical characteristics of the prepared materials, by using X-ray diffraction (XRD), scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDS), high-resolution transmission electron microscopy (HR-TEM), X-ray photoelectron spectroscopy (XPS), Raman analysis, UV-Vis diffuse reflectance spectroscopy (DRS), Photoluminescence (PL) spectroscopy studies. Based on XRD analysis data, BiVO4 exhibits a phase change of the tetragonal structure to monoclinic at 500 °C (BiVO4@500 °C). It is interesting to note that under sunlight irradiation, BiVO4 nanoparticles annealed at 500 °C show excellent photocatalytic behavior in opposition to the dye methylene blue (k = 0.0151 min-1). According to investigations on the development of antibacterial activity through the utilization of BiVO4@500 °C sample by well diffusion method appears to be an effective growth inhibitor of both gram-positive and gram-negative bacteria, such as Bacillus subtilis (B. subtilis), Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), Proteus vulgaris (P. vulgaris)), respectively.