Graphene-conducting polymer nanocomposites for enhancing electrochemical capacitive energy storage

The evolution of power generation, expansion of transportation and electrification, and popularization of portable electronic devices have altogether posed growing demands for more efficient energy storage systems. Supercapacitors, as one of major electrochemical energy storage devices, have recently received renewed attention. In this mini review, our focus is on graphene-conducting polymer nanocomposites and their applications in supercapacitors that have potential to perform high power and energy density, fast charge/discharge rate, low cost and eco-friendly operation conditions. We first introduce major types of supercapacitors and their working principles. We then overview several hybrid material systems combing graphene and various conducting polymers such as polyaniline, polythiophene, polypyrrole and their derivatives, with the emphasis on the composite design, synthesis methods, capacitive performance and current applications in flexible and bendable supercapacitors. Finally, the challenges and outlook for further applications of such composite electrode materials are briefly commented with an emphasis on the perspective of future research directions.