High-Performance Fiber-Shaped Supercapacitors Enabled by Polyaniline @ MXene Ti3C2Tx Hybrid Graphene Aerogel Fiber

Developing fiber-shaped supercapacitors (FSCs) with high capacitance, high energy density, and exceptional rate performance is crucial for reliable, stable and high-performance wearable electronics. Here, a polyaniline (PANI) @ MXene Ti3C2Tx/graphene (PTG) aerogel fiber was rationally fabricated via a confined hydrothermal method followed by freeze-drying treatment. The graphene sheets construct the skeleton of the aerogel fiber, which possesses a porous and interlinked structure, providing interconnected diffusion channels and a high specific surface area that promote electrolyte migration and abundant ion adsorption sites. Moreover, the covalent modification between PANI nanoparticles and Ti3C2Tx sheets can significantly improve interfacial coupling and provide abundant redox sites, resulting in a reduced energy barrier of electron transfer, good interfacial stability and superior H+ storage capability. As a consequence, the PTG aerogel fiber electrode delivers an excellent specific mass capacitance of 484.8 F g−1, impressive rate properties (244.4 F g−1 at 10 A g−1) and exceptional cycle ability (85.2% after 5000 cycles). Additionally, the fabricated symmetrical FSC exhibits considerable electrochemical performance, including high capacitance and good energy density. This work depicts a novel route to prepare a graphene fiber-based electrode for high-performance FSCs in an intelligent wearable system.