Covalent-architected molybdenum disulfide arrays on Ti₃C₂T_x MXene fiber towards robust capacitive energy storage

Ti₃C₂T_x MXene fiber has shown extraordinary potential for supercapacitor electrode in wearable electronics and textile energy storage, but realizing high energy density and practical-powered applications remains a great challenge. Here, we report a covalent-architected molybdenum disulfide-Ti₃C₂T_x (MoS₂-Ti₃C₂T_x) core-shell fiber for high-performance supercapacitor. Benefiting from the microfluidic and micro-reaction strategies, the ordered MoS₂ arrays are strongly bridged on Ti₃C₂T_x fiber via Ti-O-Mo bond, resulting in large exposed surface, enhanced porosity and excellent interfacial conduction for charges high diffusion and faradaic transfer. The MoS₂-Ti₃C₂T_x fiber exhibits ultra-large capacitance of 2028 F cm⁻³ and admirable reversibility in 1 M H₂SO₄ aqueous electrolyte. Meanwhile, MoS₂-Ti₃C₂T_x fiber-based solid-state supercapacitor presents high energy density of 23.86 mWh cm⁻³, capacitance of 1073.6 F cm⁻³ and superior cycling ability of 92.13% retention after 20,000 cycles, which can realize stable energy supply for wearable watch, LEDs, electric fans, toy ship and self-powered devices. Our work may provide an insightful guidance for the advanced design of structural fiber towards robust new energy and next-generation wearable industry.