Enhanced photocatalytic activity of BiVO4 powders synthesized in presence of EDTA for the decolorization of rhodamine B from aqueous solution.

Bismuth vanadate (BiVO4) powders were successfully synthesized in presence of EDTA via microwave irradiation and used as photocatalysts in the oxidation reaction of rhodamine B (rhB) under visible light. Different concentrations of EDTA (0.5 to 10%) to chelate Bi3+ ions were employed on the BiVO4 synthesis. Under the presence of EDTA, a monoclinic crystalline structure was obtained, whereas a mixture of monoclinic and tetragonal phases was observed in the absence of EDTA. In addition, the use of different EDTA concentrations promoted the formation the different shapes of particles. The BiVO4 sample synthesized with low concentration of EDTA (0.5%) exhibited about 85% of rhB decolorization in 300 min at pH 7.5. Therefore, this high efficiency can be attributed to a combination of intrinsic properties such as the morphology type and monoclinic structure of BiVO4 particles.