Graphene modified vanadium pentoxide nanobelts as an efficient counter electrode for dye-sensitized solar cells

Efficient dye-sensitized solar cells (DSSCs) were fabricated using graphene modified vanadium pentoxide nanobelts (GVNBs) as a cost-effective counter electrodes (CEs). GVNBs were synthesized by facile one-step hydrothermal method without using any reducing agent and harmful solvents. These novel nanocomposite have been tested as a counter electrode in DSSCs for the first time, which showed high solar to electrical energy conversion efficiency. The GVNBs showed the excellent electrocatalytic activity for the reduction of triiodide to iodide due to the synergetic effect between one-dimensional shape of vanadium pentoxide nanobelts and reduced graphene oxide. The DSSCs based on the GVNBs CEs have reached a high power conversion efficiency of 6.17%, which is comparable to that (7.98%) of the conventional platinum (Pt)-based CEs. This result indicate that GVNBs can be used as an alternative to conventional Pt-based CEs for the highly efficient DSSCs.