Fabrication and assessment of poly(lactic acid) - poly(4-styrene sulfonate) flexible membranes as electrodes for supercapacitors

Abstract

Flexible supercapacitors have become a popular research area as an energy storage technology for powering portable gadgets because of their high areal capacitance. The present work describes the preparation of flexible films of poly(lactic acid) and poly(4-styrene sulfonate) as electrode material for supercapacitors. The techniques like Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), water contact angle (WCA), scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to analyze physicochemical properties and cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charge-discharge (GCD) were used to analyze electrochemical properties of developed flexible films. An electrode film exhibited maximum areal capacitance of 303.5 mF cm−2 at 0.2 mA cm−2 current density with energy density 15.8 μWh cm−2 and power density 243.9 μW cm−2 and showed capacitance retention of 66.69 % after prolonged 1000 cycles. The fabricated micro supercapacitor device achieved an areal capacitance of 490.3 mF cm−2 at 0.3 mA cm−2 current density, which provides a platform for making large-scale supercapacitor devices for industrial applications.