Preparation of size-tunable SnS2 nanocrystals in situ adjusted by nanoporous graphitic carbon nitride in the process of hydrothermal synthesis with enhanced photocatalytic performance

A series of size-tunable SnS2 nanocrystals in situ adjusted by nanoporous graphitic carbon nitride (npg-C3N4) in different mass ratios (5:100-20:100) to the SnS2 products during hydrothermal synthesis were successfully prepared. The structures, Brunauer-Emmett-Teller (BET) specific surface areas, morphologies, optical properties and components of the resultant SnS2 were studied by the corresponding characterizations. The results were an undefiled hexagonal phase SnS2 without residual npg-C3N4, and the crystal sizes and energy gaps of the synthetic SnS2 gradually decreased with the increasing added amount of npg-C3N4, while the opposite trend was observed for the BET specific area. The photocatalytic performance was investigated through the visible-light driven (λ > 405 nm) photocatalytic degradation of methyl orange (MO), and the SnS2 adjusted by 5:100 npg-C3N4 showed the highest photocatalytic activity. The results of the characterizations and photocatalytic tests indicated that the use of npg-C3N4 as a template to control the size of SnS2 nanocrystals is a feasible and effective method, and it could potentially be generalized to the preparations of other nanoparticles that need size control.