Abstract: 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 (λ>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.

Key words: bismuth vanadate, photocatalysis, visible light, microemulsion