Fabrication of PEDOT:PSS/rGO fibers with high flexibility and electrochemical performance for supercapacitors

Highlights: • PEDOT: PSS/rGO fibers are prepared by easily-accessible hydrothermal confinement reaction. • PEDOT:PSS/rGO fiber with simultaneously enhanced capacitance and mechanical properties can be obtained. • The fiber-shaped supercapacitor shows a high specific energy density of 10.68 Wh• kg⁻¹ at the power density of 81.25 W kg⁻¹. -- Abstract: Implantable, flexible and easily reconfigurable supercapacitors with high power and energy densities are considered necessary for the development of portable and wearable electronics. However, obtaining a fiber-incorporating high electrochemical performance and fracture elongation remains a huge challenge. Here, we prepare a poly(3,4-ethylenedioxythiophene):poly(styrenesulfonic acid)/reduced graphene oxide (PEDOT:PSS/rGO) fiber (PGF) with high-quality electrodes for supercapacitors by easily-accessible hydrothermal confinement reaction. The optimized P₃G₇F exhibits improved electrochemical performance including a high specific capacitance (C_s) of 249.5 F g ^{− 1} at 0.5 A g ^{− 1} and good cycling stability. Moreover, after introducing the PEDOT:PSS, the elongation at break of the P₃G₇F is doubled to 13.9%. A symmetric supercapacitor (SSC) based on the P₃G₇F displays a high specific energy density of 10.68 Wh kg⁻¹ at a specific power density of 81.25 W kg⁻¹. The improved performance of the fabricated composite fiber is attributed to the unique structures of the rGO and PEDOT:PSS and their synergistic effect. This study introduces an opportunity for the development of next-generation flexible and wearable devices.