Low temperature in air molten synthesis of flower-like hierarchical structure SnS2 with superior photocatalysis

Abstract

A molten method with the characteristics of low temperature, air environment, simplicity, cost-effectiveness and easy scale-up, was tried for the synthesis of highly photocatalytically active SnS2. By heating the ground mixture of low-melting-point S and SnCl2•2H2O powders in air at 120 °C for 6 h, phase-pure SnS2 with a nanoflake-assembled flower-like hierarchical structure was obtained. The phase, purity, microstructure, and bandgap of the obtained SnS2 (SnS2-M) were determined using a series of advanced characterization means. The photocatalytic property of SnS2-M was assessed based on the reduction of aqueous Cr(VI) with visible-light (λ > 420 nm) actuation. The photocatalytic results demonstrated that SnS2-M had extraordinarily high photocatalytic activity, which was 7 times as that of SnS2 nanoplates fabricated through hydrothermal approach. Moreover, SnS2-M showed good retention of photocatalytic performance during the recyclability tests (the Cr(VI) removal ratio was 98.9% in the first cycle and 91.6% in the third cycle).