Electrochemical properties of graphene nanosheets/polyaniline nanofibers composites as electrode for supercapacitors

Graphene nanosheets/polyaniline nanofibers (GNS/PANI) composites are synthesized via in situ polymerization of aniline monomer in HClO4 solution. The PANI nanofibers homogeneously coating on the surface of GNS greatly improve the charge transfer reaction. The GNS/PANI composites exhibit better electrochemical performances than the pure individual components. A remarkable specific capacitance of 1130 F g−1 (based on GNS/PANI composites) is obtained at a scan rate of 5 mV s−1 in 1 M H2SO4 solution compared to 402 F g−1 for pure PANI and 270 F g−1 for GNS. The excellent performance is not only due to the GNS which can provide good electrical conductivity and high specific surface area, but also associate with a good redox activity of ordered PANI nanofibers. Moreover, the GNS/PANI composites present excellent long cycle life with 87% specific capacitance retained after 1000 charge/discharge processes. The resulting composites are promising electrode materials for high-performance electrical energy storage devices.

► Graphene nanosheets/polyaniline nanofibers composites are synthesized in HClO4.
► The composites effectively enhance the kinetic for charge transfer and ion transport.
► A remarkable specific capacitance of 1130 F g−1 is observed for the composite.
► The mass ratios of graphene and polyaniline affect the electrochemical performances.