Synthesis and electrochemical properties of three-dimensional graphene/polyaniline composites for supercapacitor electrode materials

To improve the specific capacitance and rate capability of electrode material for supercapacitors, three-dimensional graphene/polyaniline (3DGN/PANI) composite is prepared via in situ polymerization on GN hydrogel. PANI grows on the GN surface as a thin film, and its content in the composite is controlled by the concentration of reaction monomer. The specific capacitance of 3DGN/PANI composite containing 10 wt% PANI reaches 322.8 F·g^-1 at a current density of 1 A·g^-1, nearly twice as large as that of the pure 3DGN (162.8 F·g^-1). The capacitance of the composite is 307.9 F·g^-1 at 30 A·g^-1 (maintaining 95.4%), and 89% retention after 500 cycles. This study demonstrates the exciting potential of 3DGN/PANI with high capacitance, excellent rate capability and long cycling life for supercapacitors.