Synthesis of SnS₂ Nanoparticles and Their Application as Photocatalysts for the Reduction of Cr(VI)

The present study reports the synthesis of SnS₂ nanoparticles with different morphologies via a facile thermal decomposition approach. The SnS₂ nanoparticles were synthesized using tin chloride and thiourea (or thioacetamide) in two different solvents (diphenyl ether and 1-octadecene). The SnS₂ nanoparticles were extensively characterized using different analytical techniques. The crystallite size of SnS₂ varies from 6.1 nm to 19.0 nm. Electron microscopy studies indicate that the SnS₂ samples consist of flakes which assemble into different hierarchical structures such as ball dahlia, peony dahlia-like nanoflowers, nanoyarns and linear structures under different synthetic conditions. The SnS₂ nanoparticles show interesting optical properties and the band gap varies from 2.31 eV to 2.94 eV. Detailed mechanism of formation of SnS₂ nanoparticles with different morphologies has been proposed. The SnS₂ nanoparticles were explored for photocatalytic reduction of Cr(VI) in an aqueous solution in the presence of sunlight and they act as visible light photocatalysts with good activity.