Electropolymerization of aniline on carbonized polyacrylonitrile aerogel electrodes: applications for supercapacitors

Abstract

Polyaniline was electrochemically synthesized on carbon polyacrylonitrile aerogel electrodes for use as active material in supercapacitor devices. Electrochemical characterization was performed by cyclic voltammetry, electrochemical impedance spectroscopy (EIS) and charge–discharge experiments in aqueous medium. Two types of electrochemical phenomenon were observed; the first is based on electrostatic energy storage in the double layer at the interface solution/carbon polyacrylonitrile (PAN) aerogel, the other is associated with the redox processes in polyaniline, for which the faradaic charge depends on the potential range. The performance of the supercapacitor was tested for capacity, energy and power density and self-discharge. Specific capacitance as high as 230 F g⁻¹ was reached. A symmetrical supercapacitor showed good cyclability (over 3000 cycles) during repeated charge–discharge cycles. The results are very promising and demonstrate the viability of a symmetric supercapacitor based on carbon PAN aerogel covered by an electronically conducting polymer.