Microstructure and Characteristic of BiVO4 Prepared under Different pH Values: Photocatalytic Efficiency and Antibacterial Activity

Abstract

In the present study, BiVO₄ sample was prepared under different pH 0.5-13 without capping agent. Different morphology characteristics were observed, such as sheet crystal structure, cross crystal structure and branching crystal structure. The mechanism of the formation of BiVO₄ nanostructure was discussed. Under acid condition, sheet crystal structure was obtained. The phenomenon could be attributed to polymerization of vanadate in the presence of H⁺. In the weak alkaline solution, across structure and branching type morphology was obtained. The photocatalytic efficiency for the samples ranked as pH 5 > pH 3 > pH 7 > pH 9 > pH 1 > pH 11 > pH 13 > blank, which is in good agreement with X-ray diffraction (XRD) result. <i>E. coli</i> envelop was damaged in the presence of BiVO₄ under visible light. The protrusion on envelop was diminished by BiVO₄. Attenuated Total Reflection Fourier transformed Infrared Spectroscopy (ATR-FTIR) results suggested the intensity was weakened for the amide, phosphoric, -COO^- group and C-H bond in lipopolysaccharides (LPS), peptidoglycan and periplasm molecules.