Tween 80 Modified Graphene with Improved Processability for the Fabrication of Supercapacitors

To improve processability, graphene was modified with Tween 80. The amount of binder required for making graphene electrodes was reduced to 4 wt% when modified with Tween 80 thus enhancing the processability for the fabrication of supercapacitors. The Tween 80 modification has considerably improved the surface area of graphene. Specific capacitance of 194.2 F/g for aqueous electrolyte and 92.06 F/g for organic electrolyte was obtained for these supercapacitors. Cyclic voltammetry of the supercapacitors with aqueous electrolyte exhibited excellent reversibility, close to ideal behavior, whereas organic electrolyte systems showed deviation at higher scan rates due to more internal resistance. The frequency response of the supercapacitors was studied using electrochemical impedance spectroscopy and found to have excellent electrochemical stability.