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In this study, we have successfully synthesized BiVO4 materials by hydrothermal method. The degradation of methylene blue (MB) under LED visible light mediated by S2O8/BiVO4/Vis system. The obtained BiVO4 catalyst was characterized by X-ray diffraction (XRD), Raman, scanning electron microscope (SEM), and UV-visible diffuse reflectance spectrum (UV-vis DRS). We investigated the effect of S2O8 concentrate, pH value and initial concentration on the removal rate of MB. The results of XRD spectra showed that the BiVO4 fragment has a crystalline structure in moneblinite monoclinic phase alone. The degradation of MB concentration under visible light mediated S2O8/BiVO4/Vis was 78% after 100 minutes of irradiation. The band gap (Eg) of BiVO4 was estimated to be 2.39 eV. Therein, the presence of Na2SO4 anions decrease concentration of MB with compared to the original using S2O8/BiVO4 system alone.

Recently, BiVO4 photocatalysts has been received much attention in field of catalysts. Because it can be used to degrade harmful organic catalysts in visible light, irradiation produces CO2, H2O and less harmful organic matter. In this study, we have successfully synthesized a BiVO4 photocatalysts via co-precipitation method in the presence of urea and different calcined temperatures. The survey calcined temperatures as 300°C; 350°C; 400°C and 450°C. The obtained materials were characterized by Scanning electron microscope (SEM) and X-ray diffraction (XRD). The photocatalytic activity was evaluated by the photocatalytic degradation of rhodamine B (RhB) degradation under visible compact Philip lamp (40W) light irradiation. The result indicates that all samples calcined are monoclinic scheelite structure of BiVO4. The BiVO4-350°C sample performed the best in the photodegradation of RhB.

In this study, we investigated the synthesis of BiVO4 nanoparticles via the hydrothermal method and their photocatalytic activity for the degradation of methylene blue (MB) under LED visible light mediated by H2O2. The obtained BiVO4 catalyst was characterized by XRD, Raman, SEM, and UV-vis DRS. The effect of H2O2 concentrate, pH, and MB initial concentration on the removal rate of MB was carefully studied. The results showed that MB was decolorized entirely after 30 min in the BiVO4/H2O2/Vis process whereas the decomposition rate of BiVO4 with the absence of H2O2 is 78% after 60 min. The accelerated degradation of MB by in the BiVO4/H2O2/Vis process is due to H2O2 acts as the external electron acceptor, which could promote the separation of photo-induced electrons and holes.