Rational design of active layer configuration with parallel graphene/polyaniline composite films for high-performance supercapacitor electrode

For the traditional supercapacitors based on the graphene@polyaniline (PANI) film prepared by electropolymerization, the interfacial contact between the graphene substrate and PANI shell plays a vital role in improving the PANI stability and the electrochemical capacitance of the active layer. In this work, we propose a novel strategy that the reduced graphene oxide (RGO) hydrogel film with given size could be divided into two for respective PANI electrodeposition and the two graphene@PANI films are assembled parallelly on carbon cloth to obtain the supercapacitor electrode. Owing to the additional lateral RGO/PANI interface, the resulting electrode delivers a high specific capacitance of 949 F g −1 at 1 A g −1 and 760 F g −1 even at the high current density of 20 A g −1 . The corresponding binder-free symmetric supercapacitor device could attain a maximum energy density of 18.2 Wh kg −1 and a maximum power density of 4.75 kW kg −1 , with a high capacitance retention of 93.1% after 10000 charge/discharge cycles. These superior properties of the electrodes based on the parallel RGO/PANI films testify the rational design of the active layer configuration for enhanced interfacial effect. This work would provide a novel pathway towards the preparation of high-performance supercapacitor electrodes.