Bridging of adjacent graphene/polyaniline layers with polyaniline nanofibers for supercapacitor electrode materials

Graphene sheets (GNS) surface-grown with polyaniline nanorods (GP) was wrapped by Polyaniline nanofibers (GP-P) via interfacial polymerization. The polyaniline nanofibers can act as structure coupling bridges and conductive wires for linking adjacent layers of GP together, thus accelerating the charge transfer among different GP layers and enhancing the specific capacitance and rate capability of the electrode materials. The specific capacitance of GP-P can reach 578 F/g at a current density of 1 A/g. An asymmetric supercapacitor based on GP-P cathode and a GNS anode was assembled. An energy density of 18.8 Wh/kg at a power density of 1000 W/kg was obtained with a retention life of 93% after 10,000 cycles, suggesting a good cycling stability of the GP-P. The good capacitive performance of GP-P is contributed to the fact that the GP-P in the form of compact and multilayers' structures exhibits high interaction between the PANI nanofibers and GP, resulting in high resistance from mechanical damage during charge/discharge process. (C) 2019 Elsevier Ltd. All rights reserved.