Abstract:

With the rapid development of the Internet of Things, smart healthcare, and wearable electronics, there is an increasingly urgent demand for high-performance flexible energy storage devices. Supercapacitors (SCs) have emerged as promising candidates due to their high power density and long cycle life. However, conventional electrode materials often suffer from limited specific capacitance, insufficient mechanical flexibility, and poor long-term cycling stability under flexible conditions, which severely restricts their practical application. To address these challenges, this study aims to develop a novel electrode material that combines high electrochemical performance with excellent mechanical flexibility. By constructing a ternary composite of sulfur-doped graphene oxide (SGO) with two conductive polymers, polyaniline (PANI) and polypyrrole (PPy), a highly conductive hierarchical porous network is formed through the interweaving of mixed nano-sized PANI and PPy. The incorporation of sulfur atoms into SGO effectively enlarges the interlayer spacing of graphene, significantly mitigating the restacking of graphene sheets and thereby exposing more active surfaces. Electrochemical tests demonstrate that the as-prepared SGO/PANI/PPy ternary composite electrode exhibits outstanding performance, delivering a high specific capacitance of 561.8 F·g^-1. At a power density of 250.62 W·kg^-1, the device achieves an energy density of 19.51 Wh·kg^-1. Moreover, the electrode retains 98.12% of its initial capacitance after 10000 consecutive charge-discharge cycles. This work confirms the great potential of the ternary composite as an electrode for flexible supercapacitors and provides new insights into addressing the performance limitations of flexible energy storage devices through multi-component synergy and structural design.

Key words: sulfur-doped graphene, polyaniline, polypyrrole, flexible supercapacitor