Electrochemical reduction of ultrathin graphene oxide/polyaniline films for supercapacitor electrodes with a high specific capacitance

The article describes ultrathin film electrode composed of polyaniline (PANi) and electrochemically reduced graphene oxide (ERGO) bilayers, which was achieved using layer-by-layer (LBL) assembly method. The performance of the electrode composed of 30 PANi/ERGO bilayers denoted to PANi-ERGO30 was analyzed in a three-electrode cell using aqueous 1 M H2SO4 electrolytes. The electrode exhibited a specific capacitance of 1563 F/cm3 (at a current density of 3.0 A/cm3), and achieved one of new record values among carbon-based devices including conducting polymers, to the best of our knowledge. This breakthrough was made possible by the development of a unique process that minimized the morphological damage to the thin film electrodes, and prepared optimal doping and oxidation state of PANi in the multilayer films for achieving excellent electronic conductivities and ionic transport. The LBL-assembly method provides a tool for preparing well-organized homogeneous PANi/ERGO composites.