Solvents adjusted the sulfur vacancy in SnS2 nanosheets for tuned photoreduction of Cr (VI)

A new feasible idea for customizable controlling the sulfur vacancy (SV) by adjusting the solvent system in a solvothermal process was adopted to synthesize SnS2 with different concentrations of SV. SnS2 nanosheets obtained in H2O have more sulfur vacancies than those obtained in H2O/ethanol or ethanol/CS2. The introduction of SV can not only reduce the band gap of SnS2, but also promote the separation of photoinduced electrons-holes. As a result, SnS2 with the richest SV shows the best activity in photoreduction of Cr (VI), with the kinetic rate constant reaching to 0.08983 min−1, which also could be recycled after acid washing. This work reinforces the new understanding of sulfur vacancies, and provides valuable guides in rationally designing new efficient degradation photocatalysts.