Abstract: In this paper, polyaniline/activated mesocarbon microbeads (PANI/A-MCMB) composite material was obtained through in-situ chemical polymerization of aniline by using activated mesocarbon microbeads (MCMB) as substrate and ammonium peroxydisulfate (APS) as oxidizing agent. The morphology and structure of prepared PANI/A-MCMB composite material was characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD). A symmetric redox supercapacitor was assembled with PANI/A-MCMB composite as active electrode material and 1.0 mol/L H₂SO₄ aqueous solution as electrolyte, and the electrochemical properties of this PANI/A-MCMB supercapacitor were investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charge/ discharge tests. The experimental results show that the single specific capacitance of PANI/A-MCMB composite materials is 301.6 F/g at current density for 0.1 A/g, the specific capacitance is 276.3 F/g and the capacity retention is 91.6 % after 1 000 charge/discharge cycles. PANI/A-MCMB composite materials have higher specific capacity and better cyclic stability than PANI electrode materials whose single specific capacitance of PANI is only 228 F/g and the capacity retention is 39.5% after 1 000 charge/discharge cycles.

Key words: polyaniline, mesocarbon microbeads, in-situ chemical polymerization, supercapacitor