Poly(3,4-Ethylenedioxythiophene)-Graphene Composite Electrodes For Solid-State Supercapacitors with Ionic Liquid Gel Polymer Electrolyte

Abstract

Poly(3,4-ethylenedioxythiophene) (PEDOT)-graphene composite films are prepared by a novel ultrashort galvanic pulse electropolymerization technique for application in solid-state supercapacitors. Scanning electron microscopy (SEM) studies show that morphology of the composite films is significantly modified by in situ incorporation of graphene. Solid-state supercapacitor cells using PEDOT-graphene composite electrodes and ionic liquid gel polymer electrolyte were fabricated and characterized. The impedance spectroscopy studies show that the PEDOT-graphene composite electrodes have specific capacitance value of ~80 F g-1 as compared to ~72 F g-1 of PEDOT electrodes and a significantly lower ion diffusion related resistance. The PEDOT-graphene composite electrodes based cell shows specific energy ~4.1 Wh kg-1 and the corresponding specific power ~9.0 kW kg-1 in the solid-state design.