Highly Performed Fiber‐Based Supercapacitor in a Conjugation of Mesoporous MXene

Abstract With the continuous demands for wearable electronics, the embeddable power sources have drawn attention to develop advanced electrode materials and feasible manufacture procedures. Fiber‐based flexible energy storage devices have the potential to be practically integrated by utilizing the high‐performance materials with precisely constructed structures. Herein, a novel approach is presented to achieve an outstanding fiber‐based supercapacitor by simultaneous wet‐spinning of mesoporous MXene (Ti 3 C 2 T x ) nanoflakes. The volumetric capacitance of the porous fiber is enhanced up to ≈145% when the content of mesoporous MXene reaches 15 wt%. The symmetric all‐solid‐state fiber supercapacitor shows an extraordinary capability of 821.5 F cm –3 at a current density of 0.5 A cm –3 , which reflects an enormous improvement to that of a nonporous MXene fiber‐based supercapacitor. The measured energy density is 8.9 mWh cm –3 at a power density of 401 mW cm –3 , which also indicates the effective synergy of the constructed pathways for ions and electrons. This work demonstrates the feasibility of scalable production of fiber‐based electrode materials with porous MXene for powering wearable applications.