Bi2WO6 Nano‐ and Microstructures: Shape Control and Associated Visible‐Light‐Driven Photocatalytic Activities

Abstract
The shape‐controlled synthesis of nano‐ and microstructured materials has opened up new possibilities to improve their physical and chemical properties. In this work, new types of Bi2WO6 with complex morphologies, namely, flowerlike, tyre‐ and helixlike, and platelike shapes, have been controllably synthesized by a facile hydrothermal process. The benefits of the present work also stem from the first report on the transformation of Bi2WO6 from three‐dimensional (3D) flowerlike superstructures to 2D platelike structures, and on the formation of tyre‐ and helixlike Bi2WO6 superstructures. UV/Vis absorption spectra show that the optical properties of Bi2WO6 samples are relevant to their size and shape. More importantly, the photocatalytic activities of Bi2WO6 nano‐ and microstructures are strongly dependent on their shape, size, and structure for the degradation of Rhodamine B (RhB) under visible‐light irradiation. The reasons for the differences in the photocatalytic activities of these Bi2WO6 nano‐ and microstructures are further investigated.