Low platinum loading PtNPs/graphene composite catalyst with high electrocatalytic activity for dye-sensitized solar cells

Platinum nanoparticles (PtNPs)/graphene composite materials are synthesized by a controlled chemical reduction of H₂PtCl₆ on graphene sheets. The electrocatalytic activity of PtNPs/graphene composite counter electrode for dye-sensitized solar cell (DSSC) is investigated. The results demonstrate that PtNPs/graphene composite has high electrocatalytic activity for dye-sensitized solar cell. The cell employing PtNPs (1.6 wt%)/graphene counter electrode reaches an conversion efficiency (η) of 3.89% upon the excitation of 100 mW/cm² AM 1.5 white light, which is comparable to that of the cell with Pt-film counter electrode (η =3.76%). It suggests that one can use only 14% Pt content of conventional Pt-film counter electrode to obtain a comparable conversion efficiency. So it is promising to obtain high performance DSSC by using PtNPs/graphene composite with very low Pt content as counter electrode due to its simplicity, low cost, and large scalability.