In air solid state method to prepare Zr4+ doped SnS2 with increased photocatalytic activity

Abstract

• In air low temperature (180 °C) solid state preparation of Zr-SnS 2 . • Zr-SnS 2 comprises nanoflake aggregates. • Zr-SnS 2 exhibits greater activity than SnS 2 in photocatalytic reduction of Cr(VI). • Reasons behind the improved photocatalytic efficiency of Zr-SnS 2 are suggested. SnS 2 is a potential visible-light photocatalyst, but its applications are restricted by its dissatisfactory photocatalytic efficiency and unpractical synthesis methods. Here, a practical solid state method was employed to prepare Zr 4+ doped SnS 2 (Zr-SnS 2 ) for use as a more efficient photocatalyst. By heating the mixed powders of SnCl 2 •2H 2 O, ZrCl 4 and thiourea in air atmosphere at 180 °C for 5 h, Zr-SnS 2 nanoflake aggregates were prepared. The as-prepared Zr-SnS 2 exhibited greater photocatalytic Cr(VI) reduction activity under visible-light irradiation, as compared with SnS 2 . The doping of Zr 4+ can reduce the bandgap, promote the photogenerated carrier separation and transfer, and increase the specific surface area and Cr(VI)-adsorbing capacity of SnS 2 , which contribute to the improved photocatalytic efficiency of Zr-SnS 2 . The simple and low-cost solid state method is promising for scale-up production of efficient Zr-SnS 2 photocatalyst for treating Cr(VI)-contaminated water.