Bismuth tungstate is the simplest oxide in bismuth oxide-based layered perovskite, the main shapes of Bi2WO6 are like tires, efflorescent, heliciform, flake, nested, graded microspheres and nano-cage type. As a newly developed visible light catalyst, energy gap of Bi2WO6 is only 2.8eV. Because the property of material has a big relation to its size and morphology. Developing Bi2WO6 of different sizes can promote its catalytic property has become the research emphasis of Bi2WO6.
Recently, the study shows that the newly nano materials has visible light catalytic which can be applied in the solar energy conversion, decomposition of water and environmental pollution treatment. Among which bismuth tungstate has perfect visible light catalytic in the visible light and catch a lot of peaple's attention. In 2004, Tang firstly reported that Bi2WO6 can degrade organic pollutant like CHCL3 and CH3CHO.
Use the quantity ratio 2:1 of Bi( NO3)3•5H2O and Na2WO4•2H2O powder as raw material, with the assistance of surfactant PVP, hydrothermal reacting for 48h under 180 degree celsius. This method can produce Bi2WO6 nano material of fine crystallization, the higher rate of hydroxyl radical generation. After 6 hours' hydrothermal reaction, the sample is under non-crystallization status; If the reacting time is over than 72h, it can not do benefit to promote the property of visible light catalytic of Bi2WO6.