Scalable Wet-Spinning of MXene Assembly and Their Applications

MXenes, a fascinating large family of two-dimensional (2D) layered transition metal carbides and nitrides, have aroused substantial interest in various applications owing to their unprecedented ultrahigh metallic conductivity, mechanical properties, and hydrophilicity. This work demonstrates scalable, straightforward, continuously controlled, additive-free wet-spinning assembly of 2D titanium carbide (Ti₃C₂T<i>_x</i>) MXene fibers. MXene flakes are perfectly aligned under a mechanical drawing force using concentrated MXene colloids in a coagulation bath to produce Ti₃C₂T<i>_x</i> MXene fibers <i>via</i> a wet-spinning process. The wet-spun Ti₃C₂T<i>_x</i> MXene fibers demonstrated excellent electrical conductivity and mechanical properties. As a result, Ti₃C₂T<i>_x</i> MXene fiber-based miniaturized devices are promising for portable applications. Furthermore, the Ti₃C₂T<i>_x</i> MXene hybrid fibers with the synergistic effect of gas-adsorption and electronic properties significantly improved NH₃ sensing response (ΔR/R0 = 6.77%) at room temperature for wearable gas sensors. Additionally, fabricated wet-spun Ti₃C₂T<i>_x</i> MXene fibers are integrated into electrical wires to switch on a light-emitting diode light and transmit electrical signals to earphones to demonstrate their application in electrical devices. Furthermore, the wet-spun electroconductive Ti₃C₂T<i>_x</i> MXene fibers exhibited an enhanced electrochemical performance when assembled as supercapacitor applications. Thus, we envisage that these exciting features of 2D Ti₃C₂T<i>_x</i> MXene hybrid fiber materials will provide a novel pathway for designing next-generation portable miniaturized devices.