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Vol. 18 (2026)

Ultra-Stretchable Anti-Freezing Hydrogel Electrolytes Cross-Linked by Liquid Metal Particle Initiators Toward Soft Energy Storage Devices

https://doi.org/10.1007/s40820-026-02126-7
Qingshi Zhang
School of Chemical Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
Priyanuj Bhuyan
Wearable Fluidic, Inc, Suwon 16419, Republic of Korea
Que Thi Nguyen
School of Chemical Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
Xia Sun
Sustainable Functional Biomaterials Laboratory, Bioproducts Institute, Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
Kunlong Liang
School of Chemical Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
Mukesh Singh
School of Chemical Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
Subir Kumar Pati
School of Chemical Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
Xianglan Li
School of Chemical Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
Yeeshu Kumar
School of Chemical Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
Sungjune Park
School of Chemical Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea

Corresponding Author: Sungjune Park

sungjunepark@skku.edu

Nano-Micro Letters, Vol. 18 (2026), Article Number: 283

Abstract

Hydrogels are appealing for electrolyte of soft energy storage devices due to their mechanical flexibility and high ionic conductivity. Their polymeric networks containing large amount of water result in mechanical flexibility suitable for soft devices. However, high water content in hydrogels results in insufficient mechanical strength and freezing at sub-zero temperatures. Herein, we developed anti-freezing hydrogels with high mechanical strength by liquid metal (LM)-initiated free-radical polymerization. During the polymerization, we introduced stearyl methacrylate (SMA) to form hydrophobic associations, increasing the physical cross-linking density within the polymer network, resulting in desirable mechanical properties (elongation at break of 907% and tensile strength of 766 kPa). The hydrogel exhibiting ionic conductivity of 4.35 S m⁻1 at 25 °C after immersing in LiCl solution showed the slightly decreased ionic conductivity (3.39 S m⁻1) and almost maintained mechanical stretchability (elongation at break of 897%) after being stored at − 20 °C for 12 h. Supercapacitors consisted of the hydrogel electrolyte and activated carbon electrodes achieved a high areal capacitance (93.52 mF cm⁻2) due to rapid ionic mobility through the hydrogel electrolyte and retained 98% of its capacitance after 45,000 charge–discharge cycles due to enhanced polymeric network of electrolyte via LM particles-initiated polymerization and SMA-induced hydrophobic association.


Highlights:
1 Robust hydrogel electrolytes derived from liquid metal-initiated polymerization and increased hydrophobic association.
2 Anti-freezing hydrogels achieved by disrupting hydrogen bonds between water molecules.
3 Hydrogel electrolyte-enabled supercapacitors achieving high performance and mechanical deformability.

Keywords

Liquid metal nanoparticle initiator Anti-freezing hydrogel Wearable device Supercapacitor
Zhang, Qingshi, Priyanuj Bhuyan, Que Thi Nguyen, Xia Sun, Kunlong Liang, Mukesh Singh, Subir Kumar Pati, Xianglan Li, Yeeshu Kumar, and Sungjune Park. 2026. “Ultra-Stretchable Anti-Freezing Hydrogel Electrolytes Cross-Linked by Liquid Metal Particle Initiators Toward Soft Energy Storage Devices”. Nano-Micro Letters 18 (March):283. https://doi.org/10.1007/s40820-026-02126-7.
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