Low Temperature Synthesis of Tungsten Trioxide/Bismuth Tungstate Heterojunction with Enhanced Photocatalytic Activity

In this paper, the heterostructure composed of tungsten trioxide (WO3) and bismuth tungstate (Bi2WO6) was synthesized by a hydrothermal treatment at low temperature of 95 degrees C. The orthorhombic Bi2WO6 was formed on the surface of WO3 through a substitution of H2O molecules with [Bi2O2](2+) during the hydrothermal process. The transmission electron microscopy (TEM) revealed that an intimate interface was observed between the heterojunction of WO3 and Bi2WO6. The WO3/Bi2WO6 showed more UV-visible light absorption and higher photocatalytic performance compared with pure WO3 and Bi2WO6. The efficient separation of electron-hole pairs because of the special structure and spectral property of the WO3/Bi2WO6 heterojunction might account for the enhanced photocatalytic activity.