Polypyrrole/Bi2WO6 composite with high charge separation efficiency and enhanced photocatalytic activity

The recombination of photogenerated electrons and holes is a crucial factor that limits the efficiency of photocatalysis and dye-sensitized solar cells. Conducting polymers are known to have high charge carrier mobility. Herein, a polypyrrole (PPy)/Bi2WO6 composite with promoted charge separation efficiency was designed by a photocatalytic oxidative polymerization method. The photo-degradation of a typical model pollutant, phenol, demonstrated that the PPy/Bi2WO6 composite possessed significantly enhanced photo-activity than pure Bi2WO6 under simulated sunlight irradiation. The higher photo-activity was attributed to the synergetic effect between PPy and Bi2WO6. The photogenerated holes on the valence band of Bi2WO6 could transfer to the highest occupied molecular orbital of PPy, leading to rapid photoinduced charge separation and enhancing the photocatalytic activity. This work provided a new concept for rational design and development of highly efficient polymer-semiconductor photocatalysts for environmental purification under simulated sunlight.