Reduced Graphene Oxide Wrapped Polypyrrole on Carbon Cloth for High-Performance Flexible Solid-State Supercapacitors

Abstract

The nature of rigidity and low energy density of polypyrrole (PPy)-based electrodes limits their wide application in flexible energy storage devices. In this study, reduced graphene oxide (rGO) wrapped polypyrrole (PPy)/oxidized carbon cloth (OCC) (rGO@PPy/OCC) is prepared by the polymerization of pyrrole using MnO₂ as the oxidant on the surface of OCC followed by the adsorption and reduction of graphene oxide (GO). The prepared rGO@PPy/OCC electrode exhibits a high gravimetric specific capacitance of 547 F g⁻¹ at a current density of 0.5 A g⁻¹ and a high area specific capacitance of 1641 mF cm⁻² at a current density of 1.5 mA cm⁻². It nearly maintains the initial capacitance after 8000 cycles at a high scan rate of 200 mV s⁻¹ and at a large current density of 10 A g⁻¹. Moreover, the flexible rGO@PPy/OCC electrodes are used to construct flexible solid-state supercapacitors (FSSC). The FSSC based on rGO@PPy/OCC exhibits a high energy density (33.89 Wh kg⁻¹ and 101.81 µWh cm⁻²) and a capacitance retention of 95.10% after 1000 bending cycles, demonstrating the excellent cycling stability and flexibility. Therefore, it is potential for rGO@PPy/OCC as a flexible electrode to fabricate high-performance FSSC.