Bismuth tungstate, also called bismuth tungsten oxide, is the simplest oxide in bismuth oxide-based layered perovskite with CAS No. of 13595-87-4, molecular formula of Bi2WO4, and molecular weight of 1161.47000.
Currently, the main shapes of Bi2WO6 are like flake, nested, efflorescent, heliciform, tires, graded microspheres and nano-cage type. As a newly developed visible light catalyst, energy gap of Bi2WO6 is only 2.8eV. Developing Bi2WO6 of different sizes has become the research emphasis of Bi2WO6 as the property of material has a big relation to its size and morphology. For example, it can promote its catalytic property. 
Bismuth tungstate (Bi2WO6) has perfect visible light catalytic in the visible light and catch a lot of peaple's attention.
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. After 6 hours' hydrothermal reaction, the sample is under non-crystallization status.
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