A carbon nanotube reinforced functionalized styrene–maleic anhydride copolymer as an advanced electrode material for efficient energy storage applications

Abstract

In the wake of the global energy crisis, innovative materials are being developed to alleviate the energy shortage by utilizing the available sources sustainably. The present area of energy storage focuses on materials with high inherent conductivity. The extension of this approach to biocompatible polymers will provide the dual advantage of being environmentally safe and non-toxic along with enhanced electrochemical performance. Here, biocompatible feebly conducting styrene–maleic anhydride copolymer has been modified with thiadiazole to enhance its conductivity. Polymer nanocomposites have been prepared by incorporating multi-walled carbon nanotubes in different weight percentages. Modification with thiadiazole has been found to boost the conductivity of the polymer nanocomposite. The structure of the samples has been characterized using UV-Visible spectroscopy, FTIR spectroscopy and scanning electron microscopy and transmission electron microscopy. The electrochemical performance of the samples has been evaluated using cyclic voltammetry, electrochemical impedance spectroscopy and charge–discharge techniques. The modified copolymer shows enhanced specific capacitance, which is found to gradually increase on increasing the weight percentage of nanotubes in the polymer matrix up to a maximum loading of 15%. A specific capacitance of 905 F g⁻¹ at 0.5 A g⁻¹ was obtained for a 15% loading of nanotubes in the polymer matrix. The samples also exhibit good cycling stability with maximum capacitance retention. The prepared polymer nanocomposites have potential for use as an efficient eco-friendly energy storage material.