Synergetic effect of graphene sheet and three‐dimensional crumpled graphene on the performance of dye‐sensitized solar cells

Herein, an improved structure of the dye‐sensitized solar cell (DSSC) is demonstrated which is composed of surface modified fluorine‐doped tin oxide (FTO) glass with graphene (GR) sheets and TiO2 films incorporated with three‐dimensional crumped graphene (3‐D CGR)/GR sheets. The morphologies of the as‐prepared GR sheets on FTO glasses and 3‐D CGR/GR sheets/TiO2 films were observed by field‐emission scanning electron microscopy. Light harvesting and charge recombination kinetics were investigated with a solar simulator and electrochemical impedance spectroscopy analysis. In addition to the reduced charge resistance by the GR modified FTO, the enhanced dye loading capability of the 3‐D CGR, and the rapid charge transport by the 2‐D GR sheets, the power conversion efficiency was 7.2%, which was an increase of 56% compared to a “conventional” structured DSSC.