Fibrous asymmetric supercapacitor based on wet spun MXene/PAN Fiber-derived multichannel porous MXene/CF negatrode and NiCo2S4 electrodeposited MXene/CF positrode.

• MXene-carbon fiber (W-MX/CF) was prepared by the wet-spinning method. • W-MX/CF-4 (negatrode) and NiCo 2 S 4 -13@W-MX-4 (positrode) were derived from W-MX/CF. • A solid-state asymmetric fiber-shaped supercapacitor (SS-AFSSC) was assembled. • The SS-AFSSC delivered an energy density of 40.70 mWh/cm3. Fiber-shaped supercapacitors (FSSCs) are emerging potential power sources for next-generation flexible and wearable miniaturized electronic devices. However, the practical application of FSSCs is hindered by their low energy density due to limited design and constraints in fiber-shaped electrodes production. Herein, a rational design of wet spun MXene (Ti 3 C 2 T x)/PAN fibers derived multichannel porous MXene/Carbon Fiber (W-MX/CF) is reported as a negative electrode (negatrode), and ultrathin NiCo 2 S 4 electrodeposited W-MX/CF (NiCo 2 S 4 @W-MX/CF) as a positive electrode (positrode) for the fabrication of an asymmetric FSSC. It demonstrates high areal capacitance from both the negatrode (C A = 2160 mF cm−2) and positrode (C A = 1421 mF cm−2) fabricated from 80 wt% MXene loaded CF (W-MX/CF-4) with optimized multichannel porous features and faradaic NiCo 2 S 4 nanosheets arrays grown on W-MX/CF-4. Solid-state fiber-shaped asymmetric supercapacitor was assembled using NiCo 2 S 4 -13@W-MX-4 and W-MX/CF-4 as positrode and negatrode, respectively, with PVA/KOH as solid electrolyte. The device exhibits a remarkable energy density of 40.70 mWh cm−3 at a power density of 301.51 mW cm−3, demonstrating an efficient FSSC. The present work shows a novel way to enhance the performance of FSSCs by exploiting synergistic effects between MXene and carbon fiber derived from PAN, prepared by a facile wet-spinning method employing a solvent/non-solvent exchange process. [ABSTRACT FROM AUTHOR]