A controlled anion exchange strategy to synthesize Bi 2 S 3 nanoparticles/plate-like Bi 2 WO 6 heterostructures with enhanced visible light photocatalytic activities for Rhodamine B

Abstract Bi 2 S 3 /Bi 2 WO 6 semiconductor heterostructures with enhanced visible light photocatalytic activity were firstly prepared through a facile in-situ anion exchange approach at relatively low temperature, using thioacetamide as sulphur source and Bi 2 WO 6 nanosheets as precursors. Bi 2 S 3 nanoparticles decorated on the surface of 2D plate-like Bi 2 WO 6 nanosheets were analyzed by using X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy etc. Photocatalytic experiments indicate that such Bi 2 S 3 /Bi 2 WO 6 composites possess higher photocatalytic activity for the degradation of Rhodamine B under visible light irradiation in comparison with pure Bi 2 S 3 or Bi 2 WO 6 . Among Bi 2 S 3 /Bi 2 WO 6 composites with different contents of Bi 2 S 3 , the Bi 2 S 3 /Bi 2 WO 6 composite with 30% Bi 2 S 3 exhibits the highest photocatalytic efficiency. Based on the calculated energy band positions and photoluminescence spectrum, it was postulated that enhanced photocatalytic property could be ascribed to the reduction of the recombination rate of photogenerated electron–hole pairs and the heterojunction interface. Moreover, these results suggest that the heterostructured photocatalysts can be potentially applied in environmental protection and waste water treatment.