Photocatalytic activity of snow-like Bi2WO6 microcrystalline for decomposition of Rhodamine B under natural sunlight irradiation

Bismuth tungstate (Bi2WO6) microcrystalline at diverse pH values were prepared by a hydrothermal method. The prepared samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), and UV-vis diffuse reflectance spectroscopy (DRS). The Bi2WO6 microcrystalline obtained at pH = 5 shows a new snow-like morphologies composed of plates with different direction. It is also found that the visible-light photocatalytic activity of the Bi2WO6 prepared at pH = 5 is higher than that of the unadjusted one for decomposition of Rhodamine B under natural sunlight irradiation. Porous structure and large surface area are responsible for the high visible-light photocatalytic activity. (c) 2012 Elsevier B.V. All rights reserved.