Photocatalytic Property of Eu/BiVO<SUB>4</SUB> Photocatalyst by Citric Acid Sol-Gel Method

Abstract

Eu 3+ -doped BiVO4 photocatalyst was synthesized by complexing Sol-Gel method using citric acid as chelate, and characterized with X-ray photoelectron spectroscope(XPS), X-ray diffraction(XRD), scanning electron microscope(SEM), specific surface area (BET) and UV-Vis diffuse reflectance spectroscope(DRS). The photocata- lytic activity was evaluated by photocatalytic degradation of methyl orange (MO) solution under visible light. It re- vealed that pure BiVO4 and all the Eu 3+ doped samples were monoclinic phase and no peaks of any other phases or impurities were detected. It was also found that doping Eu 3+ increased the amount of V 4+ and oxygen vacancies. In addition, the light absorption edges of Eu 3+ doped BiVO4 had extended a red shift compared with that of pure BiVO4. However, Eu 3+ doping had little influence on morphology and specific surface area. The appropriate amount of Eu 3+ doping could signifcantly increase the photocatalytic activity and the highest photocatalytic degradation rate was about 95% when the Eu 3+ doping amount was 0.2%, which was more 62% than that of pure BiVO4 under 50