Growth of villi-microstructured bismuth vanadate (Vm-BiVO4) for photocatalytic degradation of crystal violet dye

Abstract

In this work, villi-microstructured Au-loaded BiVO4 photocatalysts were successfully synthesized by hydrothermal method. The as-synthesized photocatalysts were characterized by XRD, Raman, UV-Vis-DRS, PL, SEM and EDX techniques. The presence of metallic Au on the surface of Vm-BiVO4 support boosts the photocatalytic performance to degrade toxic crystal violet dye. The enhanced activities were attributed to the surface plasmon resonance (SPR) of Au which efficiently broadens the visible light response. SPR increases the electron population in Vm-BiVO4 and forms a Schottky barrier at the interface between Au and Vm-BiVO4 which enhances the separation efficiency of photoinduced charges. Various factors affecting photocatalytic degradation of crystal violet (CV) were studied to find optimum conditions. In addition, a radical trapping study indicates that ˙O2− is the main active species in the degradation process of cationic CV dye. All photocatalytic degradation reactions were monitored by UV-Vis spectrophotometry (PerkinElmer/λ-365).