CuS as bifunctional catalyst for enhancing photocatalytic degradation efficiency of Bi4Ti3O12

The photocatalytic activity of Bi4Ti3O12 is limited by the lack of active sites and rapid carrier recombination. In this work, the problems mentioned above are effectively solved by using a dual functional CuS load on the surface of Bi4Ti3O12. The CuS can be used as electron trapping sites to play a role as a cocatalyst, and form p-n junction with the Bi4Ti3O12 under irradiation through the properties of p-type semiconductor. The dual functionality of CuS effectively promotes carrier separation and enhances the photocatalytic degradation activity. The photocatalytic rate of Bi4Ti3O12 with optimal loading amount of CuS is ∼1.8 and ∼2.7 times as high as that of the Bi4Ti3O12 and the CuS, respectively. The photocatalytic mechanism of the Bi4Ti3O12–CuS system is investigated in detail. •CuS can be used as electron trapping sites to play a role as a cocatalyst.•CuS form p-n junction with Bi4Ti3O12 under irradiation through the properties.•The dual functionality of CuS effectively promotes carrier separation.