3D Frameworks with Uniform Active Material Loading for High-Performance Fiber-Shaped Asymmetric Supercapacitors

Flexible supercapacitors, as critical energy-storage components for wearable electronic devices, have attracted significant attention due to their high power density and long cycle life. Carbon nanotube (CNT) fibers are flexible, making them suitable as an electrode substrate, while their electric double-layer energy-storage mechanism limits their specific capacitance. In this work, a flexible 3D CNT sponge was constructed on a CNT fiber whose 3D porous conductive scaffold enables uniform active material loading, inherits the inherent flexibility of CNTs, and ensures structural integrity under deformation. An asymmetric supercapacitor was successfully assembled with fiber-shaped FCNTS/MoS2 as the negative electrode and FCNTS/PPy/PANI as the positive electrode; it achieved an areal specific capacitance of 340.2 mF/cm2 and maintained 85.5% capacity retention after 10,000 cycles. This work provides new insights for the development of high-performance fiber-shaped energy-storage devices.