Greatly enhanced photocatalytic activity over Bi2WO6 by MIL-53 (Fe) modification

Photocatalysis is one of the most promising techniques for degrading organic dyes under ambient conditions, due to that it has the characteristics of green and environmentally friendly. However, inhibited by the rapid recombination of the photogenerated charges and the low utilization of visible light, this process requires efficient photocatalysts to solve those problems. Herein, we report our recently finding that the MIL-53(Fe)/Bi2WO6 heterostructure as a high-efficient photocatalyst for Rhodamine B (RhB) and phenol degradation with excellent performance and photocatalytic stability. The catalytic rate constant of MIL-53(Fe)/Bi2WO6 (5 wt% MIL-53(Fe) for RhB and phenol degradation are 3.75 and 3.27 times higher than that of pur Bi2WO6, respectively. By introducing MIL-53(Fe) into Bi2WO6, the specific surface area becomes larger exposing more active sites and the band-gap width becomes narrower, which increases transfer rate of photogenerated electrons to the surface enhancing the electron-hole separation. Moreover, it also increased the absorption of visible light and improved the photocatalytic activity, which forcefully demonstrate that MIL-53(Fe)/Bi2WO6 is a promising photocatalyst for the removal of organic pollutants. Finally, the possible mechanism of photocatalytic degradation was discussed.