Controllable synthesis and visible-light-responsive photocatalytic activity of Bi _2WO _6 fluffy microsphere with hierarchical architecture

摘要

Bismuth tungstate (Bi _2WO _6) has attracted great research interest as an important visible-light-responsive photocatalyst. In this paper, we report a facile hydrothermal route for the shape-controlled synthesis of microanostructured Bi _2WO _6, without adding surfactants or templates. The results show that various morphologies of Bi _2WO _6 including coralloid spherical particles, packed nanosheets, fluffy microspheres, and plates can be obtained by adjusting the pH values of the precursors. The as-prepared porous fluffy microspheres with a hierarchical architecture synthesized at pH 8 exhibit the highest photocatalytic activity for the degradation of Rhodamine (RhB) under visible light irradiation. The photodegradation efficiency reaches as high as 99% within 20min irradiation. This enhanced photocatalytic activity can be attributed to the unique porous structure and high BET surface area of fluffy microspheres with hierarchical architecture.