Synthesis and visible light responsed photocatalytic activity of Sn doped Bi2S3 microspheres assembled by nanosheets

Abstract

Tin-doped Bi₂S₃ (TDB) microspheres assembled by nanosheets with different Sn contents were synthesized via a simple one step solvothermal method. These photocatalysts were characterized by XRD, SEM, TEM, BET, XPS and DRS. The results showed that the TDBs with a portion of Sn⁴⁺ substitution at Bi³⁺ sites in Bi₂S₃ lattice were consist of nanosheets, Sn dopant can increase the specific surface area and range of light response. What's more, the possible formation mechanism of the unique structure was discussed. It exhibits that the introduction of Sn can improve the photocatalytic activity, and 3 mol% is the optimal content of doped Sn for the degradation of RhB under visible light (λ > 420 nm) irradiation. Compared to the un-doped Bi₂S₃, the enhanced photocatalytic activities of the TDBs might be attributed to the photo-generated electrons and holes recombination were prevented by doping Sn. The EIS measurements further confirmed the better photogenerated charge carrier separation and transport efficiency of TDBs samples. Moreover, the possible mechanism of photocatalysis process and the possible active species were investigated in detail. This photocatalyst also showed good reusability during the recycled experiments.