Bismuth vanadate (BiVO4) has been investigated intensively and extensively due to its potential applications in the photocatalytic treatment of organiccontaining wastewater.In this study,Mo-BiVO4 samples were synthesized by a facile sol-gel process.These samples were characterized by X-ray diffraction (XRD),transmission electron microscopy (TEM),and ultravioletvisible (UV-Vis) diffuse reflectance spectroscopy.It is found that the phase structure of Mo-BiVO4 photocatalyst is monoclinic scheelite.The photocatalytic activities of the obtained BiVO4 samples were investigated by means of the decolorization efficiency of methyl orange (MO).The BiVO4 and Mo-BiVO4 photocatalysts show the response on the visible light.The doped BiVO4 photocatalysts show higher decolorization efficiency than that of bare BiVO4.