Self-assembling porous network nanostructure 7-aminoindole decorated reduced graphene oxide for high-performance asymmetric supercapacitor

Abstract

Abstract The design and preparation of novel green and efficient energy storage electrode materials is a crucial way to solve the problem of intermittent energy storage of renewable energy. In this paper, the composite electrode materials of rGO decorated by organic 7-aminoindole (7-Ai) molecule with the characteristics of fast reversible redox kinetics are synthesized successfully. The modified 7-AirGOs composites can not only produce extra pseudocapacitance, which greatly improve the specific capacitance, but also form a stable mesoporous nanostructure to facilitate the diffusion and transport of ions. By investigating the influence of 7-Ai molecule content on the electrochemical performance of the composite electrodes, the 7-AirGO1 electrode is chosen as the optimum electrode, which exhibits a high specific capacitance of 425.73 F g−1 at 0.5 A g−1 and an excellent rate capability with the current density increased to 20 A g−1. Furthermore, the asymmetric supercapacitor assembled by the 7-AirGO1 and AC as positive and negative electrode respectively delivers an energy density of 14.60 W h kg−1 and a power density up to 10,500 W kg−1, as well as a cycling stability with a capacitance retention of 97.98% at a current density of 4 A g−1 for over 20,000 cycles. These results indicate that rGO-aminoindole composites are of great potential in flexible and wearable micro energy storage devices.