One-step synthesis of polyaniline nanowire/self-supported graphene composite with excellent cycling stability

The polyaniline nanowire/self-supported graphene (PANI/SGr) composite was synthesized by one-step electrochemical exfoliation and electrodeposition method using graphite paper. The directional migration of electrolyte ions and the electropolymerization of aniline monomers through the electrical field simultaneously occurred in the mixed solution including Na2SO4, HCl and aniline (An) monomers. The stability of the PANI/SGr composite is enhanced by the combination of the new-born SGr with high activity and PANI. The uniform distribution of the nanowire-like PANI is achieved on the surface of the SGr. The PANI nanowires lead to the formation of the three-dimensional network architecture, where the existence of pores facilitates the diffusion of electrolyte ions into the internal structure of the PANI/SGr composite. The electrochemical tests of the PANI/SGr composite were conducted as a supercapacitor electrode material. The specific capacitance of 453 F·g−1 at a scan rate of 2 mV·s−1 is achieved. The rate capability of the PANI/SGr composite at the current densities of 0.5-10 A·g−1 is up to 73.1%. The cycling stability of the PANI/SGr composite is as high as 87.3% after 10000 discharge-charge cycles at the current density of 1 A·g−1. All of these results indicate that the PANI/SGr composite possesses good capacitive performance and excellent cycling stability. The PANI/SGr composite is promising for supercapacitor electrode materials.