Synthesis of Novel Visible Light Driven BiVO4 Photocatalysts via Microemulsion Process and its Photocatalytic Performance

The novel visible-light-driven BiVO4 photocatalyst with tetragonal and monoclinic structures was synthesized via a reverse microemulsion method using Bi(NO3)(3) and NH4VO3 as starting materials. The as-prepared BiVO4 samples were characterized by X-ray diffraction (XRD), scanning electron microscope SEM) and X-ray photoelectron spectroscope (XPS). The photocatalytic activity of the BiVO4 powders was determined by degradation of methyl orange molecules in water under visible light irradiation (lambda > 400nm). The results revealed that the particle and crystallite sizes of the BiVO4 powders significantly depended on synthesis temperature of the reverse microemulsion solutions. The photocatalytic tests indicated that the synthesis temperature of the microemulsion solutions can significantly affect the visible light driven photocatalytic activities. The highest methyl orange degradation of 99.9% within 3h was achieved on the BiVO4 samples with mixed tetragonal and monoclinic phases.