▎ 摘　　要

MnO2 nanowires were synthesized through the hydrothermal method that is used to fabricate the nanocomposite of polyaniline, MnO2, and Graphene nanoplatelets. The nanocomposites MnO2/polyaniline/Graphene-nano-platelets-1 (MPG-1) and MnO2/polyaniline/Graphene nano-platelets-2 (MPG-2) were synthesized by in-situ polymerization of aniline monomer in the presence of surfactants e.g., N-N-N-cetyltrimethylammonium bromide (CTAB) and ammonium persulfate (APS) under ice-cold conditions. A homogenous dispersion of graphene nanoplatelets within the polymer was achieved due to the good surfactants. Due to moderate reaction conditions, the structural and electrochemical properties of all materials e.g. nanowires and nanocomposites were well maintained. These chemical, thermal, electrical, and structural properties were studied through SEM, XRD, TGA, FTIR, and electrochemical characterizations. The nanocomposite electrode materials were used for super capacitive characterizations and had shown a high specific capacitance of 160Fg(-1), 218Fg(-1), and 330Fg(-1) at 5 mVs(-1) current density with good cyclic stability. These synthesized electrode materials exhibited very good energy and power densities with the value of 5.63 similar to Wh/kg and 1417.34 W/kg respectively at different scan rates.