Electrochemical Capacitance Properties of Electrode Based on Polyaniline Coated Graphite Nanoplatelets/Polystyrene Composite Film

Abstract The electrochemical behavior of the electrode material based on composites of polyaniline (PANI), graphite nanoplatelets (GnP), and polystyrene (PS) matrix was evaluated by applying cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectroscopy (EIS), for its application in electrochemical supercapacitor which is an advanced energy storing device. Composites were prepared by coating polyaniline on graphite nanoplatelets (PANI/GnP) via in situ emulsion polymerization, exhibiting specific surface area of 178.75 m2/g as compared with 72.1 m2/g of pristine GnP. The PANI/GnP was then embedded in polystyrene matrix (PANI/GnP/PS), which showed improved electrical conductivity due to an interconnected mesh of PANI/GnP as confirmed by scanning electron microscopy (SEM) morphological analysis. The formation of porous conductive network in PANI/GnP/PS with conductivity value of 8.6 × 10−3 S/cm resulted in high specific capacitance of 411.3 F/g measured at a current density of 0.5 A/g which corresponded to specific energy of 47.94 Wh/kg and specific power of 281.94 W/kg, as well as the decrease in specific capacitance was 32% even after 1600 charge–discharge cycles showing good rate performance which renders it an ideal material for electrodes in supercapacitors.