Transparent graphene oxide–Pt composite counter electrode fabricated by pulse current electrodeposition-for dye-sensitized solar cells

• Graphene oxide (GO)–Pt composite counter electrode was fabricated by pulse current (PC) electrodeposition.
• GO–Pt composite showed improved catalytic activity.
• DSSC with GO–Pt counter electrode exhibited best efficiency of 7.10%.

To use as counter electrode in dye-sensitized solar cells (DSSCs) highly transparent graphene oxide (GO)–Pt composite film was fabricated via spin-coating of synthesized GO followed by pulse current (PC) electrodeposition of Pt, which has many benefits such as controlling of particle size and density, remarkable adhesion, uniform morphology, and simple and atmospheric pressure method without any use of vacuum systems. Compared to GO counter electrode, uniform distribution of Pt nanoparticles with a size of ~ 30 nm on GO leads to dramatic improvement of electrocatalytic activity toward the I3− + 2e− = 3I− reaction, and thus overall power conversion efficiency was increased from 3.99% to 7.10%. Moreover, GO–Pt composite counter electrode showed superior characteristics to PC electrodeposited Pt counter electrode showing ununiform distribution of Pt nanoparticles on rough fluorine-doped tin oxide (FTO) coated glass substrates.