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Page 38 of 57 Zheng et al. Soft Sci. 2026, 6, 32

capabilities in parallel with MXene-based strain sensors. For example, Zhou et al. described a hierarchical
carbon strain sensor that, by creating a crack-propagation-controlled conductive network, simultaneously
achieves great sensitivity (range factor > 800) and an ultra-wide operational range (> 300%) [160] . This work
provides important insights for the ongoing optimization of fiber-based wearable electronics by illuminating
how structural design concepts, similar to those used in MXene fiber sensors, can overcome the
long-standing trade-off between sensitivity and stretchability. Moreover, by combining two different sensing
systems into a single fabric system, Ma et al. created integrated “dual-sensing” smart textiles . They utilized
[60]
traditional core-sheath yarn technology for tension sensing, which involves twisting conductive
rGO/CNT-coated PAN fibers around a PU core filament to create helical core-sheath yarns. Under tension,
the contact resistance between the twisted conductive fibres monotonically decreases, generating a negative
pressure-resistance effect. Two layers of MXene-coated conductive fabric are positioned between a
three-dimensional spacer fabric filled with Ecoflex elastomer to form the capacitive sensor that makes up
TM
the pressure-sensing component. The sensor has compressibility and quick recovery because to this
three-dimensional spacer construction. Through array weaving, both sensors are seamlessly incorporated
into knitted clothing that is extremely stretchy. As shown in Figure 13D-F , the system concurrently detects
[60]
and distinguishes tensile strain (up to 90%) and pressure (up to 110 kPa) without mutual interference by
independently monitoring resistive changes in the core-sheath yarn and capacitive fluctuations in the
pressure sensor.

MXene’s huge specific surface area and abundance of surface functional groups provide it sensitive resistance
responses and a significant adsorption capacity for gas molecules and biomarkers in the areas of chemical
and biomolecular sensing. Lee et al. created MXene/rGO hybrid fibers for ambient gas monitoring that
showed excellent signal stability after 2,000 bending cycles and a far better response sensitivity to ammonia
(NH ) at room temperature than single-component fiber sensors . MXene sensors built on flexible natural
[37]
3
rubber substrates provide a viable method for non-invasive breath analysis by detecting volatile organic
compounds like ethanol [161] . Additionally, MXene has been investigated for use in biomedical sensing,
including the integration of electrospun fibers for glucose monitoring . Nevertheless, the majority of these
[162]
biosensors are still in the lab’s proof-of-concept phase. Before practical implementation is possible,
important issues like selectivity, long-term stability, signal drift, and biocompatibility in complicated
wearable contexts must be methodically resolved.

Adaptable energy harvesting and storage
Because of their high intrinsic conductivity and abundance of electrochemical active sites, MXene-based
conductive fibers emerge as an ideal material platform for building fiber-based energy storage and harvesting
systems, meeting the pressing need for flexible, lightweight, and integrable power units in wearable
electronics. High volumetric capacitance and metallic-like conductivity are characteristics of MXene
materials, such as Ti C T . Through techniques like wet spinning, these characteristics can be successfully
[21]
3
2 x
transmitted to macroscopic fibers. For example, Zhang et al. generated pure Ti C T MXene fibers with a
3
2 x
volumetric capacitance of about 1,265 F·cm and a conductivity as high as 7,750 S·cm , exceeding several
-3
-1
fibers made from other two-dimensional materials (e.g., rGO) in capacitive performance .
[33]
However, pure MXene fibers frequently have restricted mechanical characteristics. Researchers have created
two primary approaches to attain performance balance in order to overcome this: coatings and composites.
Guo et al. pioneered the preparation of MXene/CNT composite fibres via hydrospinning, employing
liquid-crystalline CNTs as a scaffold to embed MXene nanosheets and prevent their re-stacking [163] . This
hybrid fiber functions as a porous substrate with excellent conductivity. A core-shell structured
MnO @MXene/CNT fiber system was then created by electrochemically depositing a MnO shell onto the
2
2
surface of the pre-fabricated MXene/CNT fibers under carefully regulated conditions (1.3 V, 20 min). In this