Perspectives of conducting polymer nanostructures for high-performance electrochemical capacitors

The production of energy using renewable energy sources and its storage has gotten attention towards the advancement of the modern world due to the depletion of fossil fuels and growing energy demands. In this respect, energy storage devices like an electrochemical capacitor, with high specific capacitance (C_s), power density, excellent cyclic stability, longer life span, fast charging-discharging rates, become a stronger prospect and a major research area worldwide. The performance of this technology mainly relies on the type of active materials used in the electrode. Many researchers have focused on the development of electrode materials in one dimensional (1D) nanostructure morphologies such as nanowires, nanorods, nanotubes, nanobelts, nanofibers, and nanoneedles to enhance the energy storage ability as well as the efficiency of electrochemical capacitors due to its anisotropic growth and large aspect ratio. In this regard, 1D conducting polymers nanostructure morphologies are found to be highly desirable owing to their fast charge-discharge chemical kinetics, tunable morphology, rapid doping-dedoping capability, and larger surface area. Nevertheless, their sole basically limits the use mainly due to low specific capacitance and poor cyclic stability, which could be overcome by developing conducting polymer-based composites to have a synergic effect delivering desired properties. Herein, the review article mainly focuses on the varieties of conducting polymers based 1D nanostructures and their composites as prospective electrode materials for development of supercapacitors to serve the energy needs of society. A comprehensive view of recent progress and future outlook has been included.