A facile preparation strategy for Bi2O4/Bi2WO6 heterojunction with excellent visible light photocatalytic activity

In this work, we provide a facile method to synthesize Bi2O4/Bi2WO6 heterojunction by a two-step hydrothermal. Bi2O4 micro-rods are in-situ generated on the surface of Bi2WO6 microspheres. Compared to pure Bi2WO6, the photocatalytic activity for the Bi2O4/Bi2WO6 heterojunction was enhanced 5 folds in degradation of Rhodamine B. In the degradation of Methyl Orange, the enhanced factor could reach to 90 folds under visible light. The superior activity could be attributed to the rapid separation and transfer of photogenerated charge carries, which could be proved by photocurrent test and electrochemical impedance spectroscopy (EIS). Moreover, the active material trapping experiments proved that( )center dot O-2(-) and h(+) are the main active species in the degradation process. The present work provides a new sight for the fabricating of visible light-driven photocatalyst with high efficiency.