Graphene Sheet/Porous NiO Hybrid Film for Supercapacitor Applications

Abstract We report the preparation of a nickel‐foam‐supported graphene sheet/porous NiO hybrid film by the combination of electrophoretic deposition and chemical‐bath deposition. The obtained graphene‐sheet film of about 19 layers was used as the nanoscale substrate for the formation of a highly porous NiO film made up of interconnected NiO flakes with a thickness of 10–20 nm. The graphene sheet/porous NiO hybrid film exhibits excellent pseudocapacitive behavior with pseudocapacitances of 400 and 324 F g −1 at 2 and 40 A g −1 , respectively, which is higher than those of the porous NiO film (279 and 188 F g −1 at 2 and 40 A g −1 ). The enhancement of the pseudocapacitive properties is due to reinforcement of the electrochemical activity of the graphene‐sheet film.