Ultrathin SnS2 nanosheets with exposed {001} facets and enhanced photocatalytic properties

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 (lambda > 420 nm), 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. (C) 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.