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

•In air low temperature (180 °C) solid state preparation of Zr-SnS2.•Zr-SnS2 comprises nanoflake aggregates.•Zr-SnS2 exhibits greater activity than SnS2 in photocatalytic reduction of Cr(VI).•Reasons behind the improved photocatalytic efficiency of Zr-SnS2 are suggested. SnS2 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 Zr4+ doped SnS2 (Zr-SnS2) for use as a more efficient photocatalyst. By heating the mixed powders of SnCl2·2H2O, ZrCl4 and thiourea in air atmosphere at 180 °C for 5 h, Zr-SnS2 nanoflake aggregates were prepared. The as-prepared Zr-SnS2 exhibited greater photocatalytic Cr(VI) reduction activity under visible-light irradiation, as compared with SnS2. The doping of Zr4+ can reduce the bandgap, promote the photogenerated carrier separation and transfer, and increase the specific surface area and Cr(VI)-adsorbing capacity of SnS2, which contribute to the improved photocatalytic efficiency of Zr-SnS2. The simple and low-cost solid state method is promising for scale-up production of efficient Zr-SnS2 photocatalyst for treating Cr(VI)-contaminated water.