Effect of ethylene glycol on the growth of hexagonal SnS 2 nanoplates and their optical properties

Abstract

Hexagonal SnS 2 particles were synthesized via a solvothermal method using a mixture of ethylene glycol (EG) and distilled water as solvent. Hexagonal SnS 2 nanoplates of more regular morphology were obtained when the volumetric ratio of EG to distilled water (EG:H 2O) decreased from 4:1 to 1:4. The effect of EG on the growth of hexagonal SnS 2 nanoplates was investigated and a growth restraint mechanism in [0 0 1] was proposed. A large band gap of 3.52 eV of the hexagonal SnS 2 nanoplates may facilitate electron injection from photo-excited dye molecules in dye-sensitized solar cells (DSSCs). A photoluminescence (PL) peak at 761 nm under excitation at 507 nm was also observed in the hexagonal SnS 2 nanoplates. The 761 nm emission, which is within the absorption band of the Ru-based dye, is expected to make sufficient utilization of solar energy in DSSCs.