NiS₂/Reduced Graphene Oxide Nanocomposites for Efficient Dye-Sensitized Solar Cells

NiS₂ nanoparticles and nanocomposites of NiS₂ with reduced graphene oxide (NiS₂@RGO) have been successfully prepared via a facile hydrothermal reaction of nickel ions and sulfur source in the absence or presence of graphene oxide. NiS₂@RGO nanocomposites exhibit excellent electrocatalytic performance for reduction of triiodide, owing to the improved conductivity and positive synergetic effect between NiS₂ and RGO. As a consequence, the dye-sensitized solar cell with the NiS₂@RGO counter electrode (CE) produces a power conversion efficiency of 8.55%, which is higher than that (7.02%) for the DSSC with the NiS₂ CE, higher than that (3.14%) for the DSSC with the RGO CE, and also higher than that (8.15%) for the DSSC with the reference Pt CE under the same conditions