Sulfur-doped Sn3O4 nanosheets for improved photocatalytic performance

Sn3O4 has shown great potential in photocatalytic water purification and energy conversion. However, it is still suffering from limited visible light-harvesting ability and sluggish charge-carrier separation. Nonmetal heteroatom doping is considered as an effective strategy to regulate the electronic structure and improve the photocatalytic performance. Herein, S-doped Sn3O4 was synthesized by a simple hydrothermal method using L-cysteine as sulfur source. It was found that the hierarchical flower-like structure of Sn3O4 would be destructed gradually by sulfur (S) doping. Nevertheless, the as-obtained S(1%)-doped Sn3O4 exhibits remarkable improved photocatalytic degradation performance of azo-dye methyl orange (MO) and antibiotic metronidazole (MTZ). S doped on the lattice of Sn3O4 can narrow the band bap to enhance sufficient photoadsorption, facilitate separating the charge carriers and producing the predominant active species (O2·-) compared with pristine Sn3O4 photocatalyst, resulting in the enhancement of MO/MTZ photogradation activity. This work demonstrates a simple route for S doping in Sn3O4 and provide guidance for the controllable design and synthesis of high-efficient photocatalysts by nonmetal heteroatom doping.