Hydrothermal Synthesis and Photocatalytic Properties of Bi_2WO_6

Series of bismuth tungstate(Bi2WO6) catalysts were synthesized through simple hydrothermal route and characterized by X-ray diffraction(XRD),field emission scanning electron microscope(FESEM) and UV-Vis diffuse reflectance spectroscope(DRS).The effects of synthesis conditions on the morphologies and properties of products were studied.UV-Vis diffuse reflectance spectra indicated that the samples had absorption in both UV and visible light areas.Their photocatalytic activities were determined by photodegradation of Rhodamine B(RhB) under UV and visible light irradiation(λ 420 nm).The results indicated that sample reacted at 180℃ for 24h(pH=2) had the best photocatalytic activities,with reaction rate constant k of 0.03688/min.The stability of photocatalysts was estimated,no obvious loss of photocatalytic property was detected after four cyclic tests.After 150min visible light irradiation,the degradation rate of dye to the Bi2WO6 reacted at 180℃ for 24h(pH=2) reached 38%.