Electrodeposition of Graphene/Polypyrrole Electrode for Flexible Supercapacitor with Large Areal Capacitance

In this study, graphene/polypyrrole (RGO/PPy) electrodes with porous structures were prepared by electrochemical codeposition and reduction. The porous structure not only enhances the effective contact area of the electrodes but also actively promotes the diffusion efficiency of the electrolyte ions. As a result, a maximum capacitance of 1091.2 mF·cm^–2 at 1 mA·cm^–2 is achieved for the 0.2-RGO/PPy electrode prepared using the deposition solution containing 0.2 mg·mL^–1 of GO. The 0.2-RGO/PPy maintains a capacitance of 78.4% at 10 mA·cm^–2. In particular, the 0.2-RGO/PPy-based supercapacitor exhibits a stack capacitance of up to 28.3 F·cm^–3. Furthermore, the supercapacitor exhibits excellent mechanical flexibility with a 93.3% capacitance retention, even under 180° bending. This study demonstrates the significant potential of RGO/PPy electrodes for high-performance energy storage systems.