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Page 2 of 19 Huang et al. Soft Sci. 2025, 5, 24 https://dx.doi.org/10.20517/ss.2025.07

sensitivity and strong robustness against external disturbances. Moreover, it serves as a reliable electrode for
electromyography signal detection, providing a high signal-to-noise ratio and low interfacial impedance. By
integrating deep learning algorithms, the organohydrogel sensing system achieves 100% accuracy in ball sports
identification, showcasing its potential for multimodal sensing platforms.

Keywords: MXene-composited organohydrogel electronics, robust interface adhesion, self-healing, environmental
adaptability, multimodal sensor, deep learning-facilitated sports recognition

INTRODUCTION
Flexible electronic platforms that replicate the features and functions of natural skin by converting external
stimuli (e.g., strain and temperature) into electrical signals have garnered significant attention and find
broad applications in electronic skin, artificial intelligence, and healthcare monitoring . Among various
[1-4]
options, conductive hydrogels (CHs) are particularly promising due to their tissue-like properties, stimuli
responsiveness, and satisfactory conductivity, making them an ideal platform for flexible electronics .
[5]
However, practical applications often involve exposure to extreme thermal environments (e.g., both cold
and hot conditions), which pose significant challenges to the mechanical properties and functionality of
CH-based electronics with high water content, severely limiting their operational range and long-term
applicability . Therefore, developing CH-based electronics with enhanced environmental adaptability,
[6]
while maintaining inherent advantages of hydrogels, is critical for expanding their practical applications.

Typically, to improve the water retention ability, introducing non-volatile solvents [i.e., glycerol (GL),
ethylene glycol, or dimethyl sulfoxide] with low vapor pressure into the hydrogel system is one of the
efficient ways to lock water molecules within the polymeric network . For example, an organohydrogel
[7]
made from a GL/water mixture maintained flexibility and excellent sensory behavior between -18 and
60 °C . The formation of strong hydrogen bonds between organic solvents and water molecules helps to
[8]
prevent water crystallization at low temperatures and improve evaporation enthalpy, thus providing
excellent environmental stability and expanding working range of the organohydrogel . However, a trade-
[9]
off between environmental stability and compromised electrical conductivity arises in the presence of
organic solvents. To address this problem, conducting components, such as carbon nanotubes ,
[10]
[11]
graphene , and MXene nanosheets , have been incorporated into hydrogels to create nanocomposite
[12]
hydrogels. Among these, MXene nanosheets, an emerging class of two-dimensional inorganic materials, are
particularly attractive for constructing flexible MXene-composited hydrogel sensors due to their excellent
hydrophilicity and sensitivity to electrical conductivity changes based on interlayer spacing . However,
[13]
when negatively charged MXene nanosheets are incorporated into the hydrogel, aggregation and
precipitation often occur during preparation, hampering efficient electrical signal transport in flexible
sensors .
[14]
[15]
[10]
Biomass polysaccharides, such as cellulose and chitosan (CS) , contain abundant hydroxyl and carboxyl
groups, enabling MXene nanosheets to be evenly integrated into the hydrogel through hydrogen bonds. The
successful stabilization of MXene nanosheets driven by cellulose nanocrystals to construct stable CHs
illustrates this approach . Therefore, incorporating polysaccharides into the hydrogel can ensure the stable
[16]
dispersion of MXene nanosheets, which is advantageous to the construction of perfect conductive path.
Moreover, while recent studies on MXene-based hydrogels primarily focus on improving mechanical or
electrical properties, they often overlook other essential properties such as self-adhesion and self-healing,
which are crucial for the practical use of CHs. Therefore, constructing stable MXene-composited
organohydrogel with multifunctionality via a simple approach remains a significant challenge.