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mechanisms, and enhanced performance benefits. Finally, we present a critical perspective on the opportunities and
challenges facing graphene and MXene fibers in the pursuit of practical, large-scale wearable applications. Owing to
their unique combination of properties, graphene and MXene fibers establish a robust platform for advanced
wearable electronics and pave the way for next-generation smart textiles.

INTRODUCTION
Driven by advances in Internet of Things (IoT), artificial intelligence (AI), and flexible electronics, smart
textiles have evolved from merely providing warmth and decoration to becoming vital components of
wearable technology. Today, they are spearheading innovations in personal healthcare, thermal
management, energy storage, human-machine interfaces, and real-time physiological monitoring . Central
[1-5]
to this evolution are soft conductive fibers, the fundamental functional units whose performance critically
determines the integration level and reliability of the entire smart textile system . Consequently, the
[6]
development of flexible conductive fibers that harmonize exceptional mechanical strength, high electrical
conductivity, and superior flexibility has become a key focus for both academia and industry. While
traditional metal-based fibers (e.g., stainless steel, silver) offer high conductivity, their practical applications
are hampered by inherent drawbacks such as high density, stiffness, and susceptibility to corrosion. Despite
their lightweight and flexible qualities, carbon nanotube (CNT) fibers still have issues with uniformity from
batch to batch and high production costs. As shown in Table 1, we have gathered important performance
indicators and cost-related features for typical conductive fibers to offer a clear benchmark reference.
Because of their inherent superior mechanical, electrical, and chemical capabilities, inherent flexible
conductive low-dimensional nanomaterials such as graphene and MXenes, have emerged as perfect building
blocks for creating next-generation high-performance soft conductive fibers . This assembly procedure is
[7-9]
schematically depicted in Figure 1A, which shows how discrete graphene and MXene nanosheets are
arranged in an orderly stack and orientation to create continuous macroscopic fibers. This is an essential step
in converting their remarkable nanoscopic inherent qualities into macroscopic conductive fibers that benefit
for smart textile applications.

Among these, graphene, a two-dimensional material made of a single layer of carbon atoms in sp 2
hybridization, is well-known for having a carrier mobility of 200,000 cm ·V ·s and a theoretical strength of
2
-1 -1
about 130 GPa. Its application exploration in electronics, composite materials, and energy areas has begun
since Andre Geim and Kostya Novoselov’s first successful isolation and independent existence verification
via mechanical exfoliation in 2004 . Graphene fiber (GF) research began in 2011 when Xu and Gao created
[10]
macroscopic GFs by wet-spinning and chemical reduction based on the solution-induced liquid crystal
phenomena of graphene oxide (GO) . By using large-sized GO sheets in conjunction with an ion
[11]
crosslinking technique, the team increased the fiber’s tensile strength to 501.5 MPa in 2012 . Related studies
[12]
were then carried out by several worldwide study groups. By modifying sheet size and solidification bath
composition, respectively, Xiang et al. and Jalili et al. improved fiber mechanical characteristics. By
[13]
[14]
using a “co-stacking of large and small sheets” technique in conjunction with high-temperature heat
treatment, Xin et al. made history in 2015 by enabling GF tensile strength to surpass 1 GPa for the first
time . Researchers then used novel techniques like microfluidic spinning , fine-denier spinning , and
[16]
[15]
[17]
plasticization mechanisms to further improve the interior fiber structure, greatly improving sheet
[18]
orientation and packing density. As of right now, high-performance GF has substantially outperformed
many conventional synthetic fibers in terms of tensile strength (up to 5.19 GPa) and electrical
[19]
conductivity (up to 1.2 × 10 S·cm ), providing a strong material basis for its use in smart textiles.
[18]
6
-1
Since its first successful production in 2011 by Naguib et al. using hydrofluoric acid etching of the MAX
phase, MXene has attracted a lot of attention as a new member of the two-dimensional material family .
[20]
This widespread interest is directly attributed to its distinctive crystal structure and rich surface chemical