Preparation and characterization of Sn-doped In2.77S4 nanosheets as a visible-light-induced photocatalyst for tetracycline degradation

Semiconductor photocatalysis technology is a promising method to solve the antibiotics pollution in water. Herein, a series of Sn-doped In 2.77 S 4 (Sn-In 2.77 S 4 ) hybrid photocatalysts for tetracycline degradation have been fabricated via a one-step hydrothermal process. The analytic results exhibit that doping Sn can improve the photocatalytic performance of In 2.77 S 4 nanosheets under the visible light illumination and the doping amount obviously affects the photocatalytic performance of the samples. When the theoretical molar ratio of Sn 4+ to In 3+ is 0.04:1 (4%), the photocatalytic efficiency of the Sn-In 2.77 S 4 photocatalyst exhibits the highest of 87.4% in comparison with 39.2% of pure In 2.77 S 4 in 20 min. Moreover, its band gap energy has been reduced to 1.56 eV from 1.75 eV and the light absorption range has been broadened. The transfer rate and separation efficiency of photo-generated electron and hole pairs of the samples have also been enhanced. In addition, the holes play a leading role in the photocatalytic degradation process.