Graphene Dispersed Bi2WO6 Nanosheets with Promoted Interfacial Charge Separation for Visible Light Photocatalysis

Graphical On the tip of my tung : A novel bismuth tungstate nanosheets photocatalyst dispersed by graphene is fabricated through PVP assisted assembly of Bi 2 WO 6 nanostructures and simultaneously reduced graphene oxide. The well dispersion of Bi 2 WO 6 nanosheets by graphene provides enhanced separation/transfer of photogenerated charges and exposed active sites for interfacial charge transfer, giving enhanced visible light photocatalytic activity compared with other similar photocatalysts. Promoting photogenerated charge separation is the key and bottleneck step in photocatalysis, which mainly determines the efficiency of solar energy conversion. Reduced graphene oxide (rGO) has been emerging in the fields of physics, catalysis and material sciences due to its unique structures, high catalytic activity and tunability. In this work, we introduced rGO nanosheets as support to fabricate uniformly-dispersed Bi 2 WO 6 nanostructures onto the rGO surface under hydrothermal condition. The resulted rGO/Bi 2 WO 6 composite exhibited superior performances in degradation of various kinds of environmental pollutants including dyes and phenol. Further electrochemical characterizations including open circuit potential, electrochemical impedance spectroscopy and electrochemical specific area indicated that incorporation of rGO evidently accelerated the interfacial charge separation and transfer. These improvements consequently contributed to largely exposed active sites and superior photocatalytic performance. Our work presented a facile strategy to tune the interfacial charge separation in semiconductor-based photocatalysts using layered materials like graphene and its derivatives.