Two-dimensional SnS2 nanosheets exfoliated from an inorganic–organic hybrid with enhanced photocatalytic activity towards Cr(vi) reduction

Abstract

Atomic-scale thin two-dimensional materials have promising application prospects in photocatalysis due to their large reactive sites, short carrier diffusion distances and high charge separation properties. In this paper, SnS₂ nanosheets of several atomic layer thickness and with {001} facets dominating are prepared with the liquid-exfoliation method using a SnS₂/n-propylamine inorganic–organic hybrid precursor. They become semi-metallic when the thickness is reduced to 30 Å, possess effective charge separation due to a much shorter diffusion length in the [001] direction as evident from the prolonged photoluminescence lifetime, and exhibit largely improved photocatalytic activity for Cr(VI) reduction under visible light irradiation, with a rate constant six-fold larger than that of bulk SnS₂.