We report the fast synthesis of thermally reduced graphene oxide : platinum (TRGO : Pt) nanohybrids by simply spraying a GO:Pt⁴⁺ solution on a hot plate. X-ray photoelectron spectroscopy and atomic force microscopy analyses are performed to investigate the thermal reduction of GO:Pt⁴⁺ and the morphologies of the TRGO : Pt hybrid monolayer, respectively. The catalytic performance of TRGO : Pt is evaluated for the reduction of o-nitroaniline. A significant increase in the reaction rate constant for TRGO : Pt compared with pure Pt is due to facilitated electron transfer at the TRGO : Pt interface and enhanced catalytic active sites. Effective electron transfer from TRGO to Pt and significantly increased catalytic active sites in hybrids suggest that TRGO : Pt is a highly potential counter electrode material in dye-sensitized solar cells (DSSCs). The hybrid provides numerous electrons to I⁻/I₃⁻ electrolyte to reduce the recombination at the interface. As a result, the performance of DSSCs with the TRGO : Pt hybrid electrode is significantly increased by 34% in comparison with a pure Pt electrode.