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Page 4 of 19 Huang et al. Soft Sci. 2025, 5, 24 https://dx.doi.org/10.20517/ss.2025.07

Preparation of conductive PAM/CS/MXene nanocomposite organohydrogels
Multifunctional PAM/CS/MXene nanocomposite organohydrogels were prepared via free radical
polymerization. Briefly, a certain amount of PA, GL and H O was poured into a blue glass bottle and stirred
2
in a 90 °C water bath for 30 min. Then, CS (0.2 g) was dispersed into the PA/GL/H O dispersion (20 g) with
2
constant magnetic stirring at ambient temperature for 2 h to obtain a uniform and stable dispersion. After
cooling to the room temperature, AM (5 g) was added into the dispersion and stirred for 2 h until AM was
completely dissolved. Subsequently, different contents of MXene (the preparation process is detailed in the
Supplementary Materials) and MBA solution (0.325 mL, 1 wt%) were sequentially employed into the
abovementioned dispersion and magnetically stirred for 2 h. The MXene content was set as 0, 0.1, 0.2, and
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0.3 mg·g . After degassing treatment, APS solution (0.08 mL, 10 wt%) was added into the mixture and
uniformly stirred for 30 s. Then, the precursor solution was promptly poured into self-made molds and put
at 60 °C for 1 h to achieve the PAM/CS/MXene nanocomposite organohydrogels, which were defined as
PCM organohydrogel. The CS content was changed from 0 to 0.015 g·g . For convenience, the prepared
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nanocomposite organohydrogel was labeled as PCMx, where x represented the weight ratio of MXene to
total solvent (mg·g ). As a reference, PCM hydrogel was fabricated via the same method.
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RESULTS AND DISCUSSION
The ingenious design strategy and fabrication procedure of PCM nanocomposite organohydrogels are
depicted in Figure 1A, which is prepared via the one-pot polymerization by incorporating CS-encapsulated
MXene nanosheets into a PAM organohydrogel within a PA/GL/water trisolvent system. The MXene
nanosheets were produced through etching and exfoliating Ti AlC with a LiF/HCl solution, resulting in
3
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high-quality, transparent nanosheets with a lateral size of 300 nm and an average thickness of 3 nm, can be
achieved [Figure 1B and C]. X-ray diffraction (XRD) patterns confirmed the successful synthesis of MXene
nanosheets [Supplementary Figure 1]. PA plays a dual role in the organohydrogel: providing an acidic
environment to ensure the complete dissolution of CS and acting as a source of free mobile ions to enhance
conductivity. Additionally, PA can anchor and crosslink with CS chains through electrostatic interaction
and hydrogen bonds . Particularly, the tendency of nanofiller-type conductive phases to slip and
[18]
recombine during deformation is a key challenge in flexible matrices . Here, abundant -NH and -OH
[23]
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functional groups of CS can form robust noncovalent interactions (hydrogen bonds and electrostatic
interactions) with the functional groups (-OH, -F, -O, etc.) on MXene nanosheets, making CS an ideal
candidate for creating stable conductive MXene nanocomplexes. To validate the protective role of CS in
stabilizing MXene nanosheets in aqueous environments, both CS-MXene and bare MXene colloidal
dispersions were stored for 10 days at ambient temperature [Supplementary Figure 2]. This enhancement in
stability improves the homogeneous distribution of MXene nanosheets within the organohydrogel, laying
the groundwork for continuous and stable conductive pathways. Meanwhile, the incorporation of non-
volatile GL can further enhance the environmental stability of the hydrogel.

Scanning electron microscopy (SEM) images of freeze-dried PCM hydrogels [Figure 1D] present the typical
interconnected microporous architecture, indicating good dispersion of MXene nanosheets within the
hydrogel matrix rather than aggregation [Supplementary Figure 3], which is beneficial to excellent
[13]
stretchability and improved sensing response . Due to the small size of the MXene nanosheets, they are
challenging to observe directly. However, energy dispersive spectroscopy (EDS) mapping images confirm
the presence and uniform distribution of MXene nanosheets within the PCM hydrogel, as evidenced by the
detection of C, N, O, and Ti elements [Figure 1E]. The chemical structure of PCM organohydrogel is
analyzed using Fourier transform infrared (FTIR) spectroscopy [Supplementary Figure 4]. To further delve
into the mechanism of interactions between different components in the PCM organohydrogel, density
functional theory (DFT) calculations were performed to simulate the molecular structure, determine the
interaction energy (E ), and verify the proposed interactions. The electrostatic potential (ESP) distribution
int