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Abstract A novel silver vanadate modified titania photocatalyst was prepared by one-pot hydrothermal method in this paper. The product was characterized by scanning electron microscope, transmission electron microscope, X-ray diffraction, X-ray photoelectron spectroscopy and UV-vis diffuse reflectance spectroscopy analysis. Methelene blue(MB) was employed to investigate its photocatalytic activity and stability, and the mechanism of the degradation of MB was also discussed according to experimental results. The results demonstrated that the photocatalytic degradation of MB by silver vanadate modified titania was a first-order reaction, and the rate constant (0.009 min-1) was three times bigger than that of P25 under visible light irradiation. The enhancement of the photocatalytic activity might attribute to the formation of coupling heterojunction between silver vanadate and titanium, and the photo-generated electrons could spontaneously migrate from conduction band of silver vanadate to conduction band of titania while the hole left on the valence band of silver vanadate to generate hydroxyl radical. The oxidation of hole as well as hydroxyl radicals played a leading role in the action. The combination of electron and receptor was the limiting step. In addition, the hybrids showed strong stability and high activity in this study. The degradation rate decreased only 4.8% after repeated for three times.
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Received: 10 April 2015
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