Defect-Elimination Strategies for Fabricating High-Strength and Highly Conductive MXene Fibers

Two-dimensional (2D) transition metal carbides and nitrides (MXenes) nanosheets exhibit outstanding mechanical, electrical, electrochemical, and photothermal conversion properties, along with good solution processability, making them highly promising for the fabrication of high-performance conductive MXene fibers. However, issues such as weak interfacial interactions, structural disorder, and nanosheet wrinkling often result in void defects, which hinder both load and electron transfer, thereby limiting the performance of macroscopic MXene fibers. This review systematically summarizes the recent progress in the defect-elimination strategies for the fabrication of high-strength and highly conductive MXene fibers, with a focus on performance and applications, from the perspectives of structure and interfacial design. Particular attention is given to strategies aimed at performance enhancement, especially those focused on strengthening interfacial interactions, improving alignment of MXene nanosheets, and eliminating voids, which are critical factors in assembling high-performance conductive MXene fibers. Meanwhile, this review highlights the diverse multifunctional applications of MXene fibers in wearable electronic textiles. Finally, we conclude by discussing the key advantages and persistent challenges associated with various assembly structures, and present an outlook on the future design and development of high-performance conductive MXene fibers, offering valuable insights for advancing research and practical applications of MXene fibers.