Ultrathin SnS2 nanosheets with exposed {0 0 1} facets and enhanced photocatalytic properties

Abstract

Hierarchical tin disulfide (SnS2) micro/nanostructures, assembled from ultrathin nanosheets with {001} facets exposed, were successfully synthesized via an l-glutatione-assisted approach. The prepared materials were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning and transmission electron microscopy, infrared spectra and UV–visible diffuse reflectance spectroscopy. The characterized results showed that these hexagonal berndtite SnS2 nanosheets selectively exposed {001} facets as the main external surfaces, and the percentage of these facets was nearly 95%. Even under visible light (λ>420nm), the products showed superior photocatalytic activity for the degradation of dye (methyl orange) and the reduction of aqueous Cr (VI). The enhanced photocatalytic properties can be attributed to the two-dimensional sheet-like nanostructure, which has a larger specific surface area and could enhance the efficiency of the electron–hole separation. The formation mechanism of the hierarchical SnS2 micro/nanostructures and its relationship with photocatalytic properties were also proposed. The result demonstrates that these hierarchical SnS2 micro/nanostructures have promising applications in the solar-energy conversion process.