Issue

Vol. 19 (2027)

Hydrophobic Eutectogels Reinforced by Zn2+-Coordinated Lignin Nanoparticles for Underwater Wearable Electronics

https://doi.org/10.1007/s40820-026-02302-9
Fuyuan Lu
Liaoning Key Laboratory of Lignocellulose Chemistry and Biomaterials, College of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, People’s Republic of China
Dan Sun
College of Chemistry and Materials Engineering, Zhejiang A&F University, Hangzhou 311300, People’s Republic of China
Wei He
Liaoning Key Laboratory of Lignocellulose Chemistry and Biomaterials, College of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, People’s Republic of China
Meng Li
Liaoning Key Laboratory of Lignocellulose Chemistry and Biomaterials, College of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, People’s Republic of China
Zhengjun Shi
The Key Laboratory of Forest Resources Conservation and Utilization in the Southwest Mountains of China Ministry of Education, Key Laboratory of National Forestry and Grassland Administration on Biodiversity Conservation in Southwest China, Yunnan Provincial Key Laboratory for Conservation and Utilization of In‑Forest Resource, Southwest Forestry University, Kunming 650224, People’s Republic of China
Yiqiang Wu
College of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, People’s Republic of China
Shao‑Fei Sun
Liaoning Key Laboratory of Lignocellulose Chemistry and Biomaterials, College of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, People’s Republic of China
Changyou Shao
Liaoning Key Laboratory of Lignocellulose Chemistry and Biomaterials, College of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, People’s Republic of China
Runcang Sun
Liaoning Key Laboratory of Lignocellulose Chemistry and Biomaterials, College of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, People’s Republic of China

Corresponding Author: Runcang Sun

rcsun3@dlpu.edu.cn

Nano-Micro Letters, Vol. 19 (2027), Article Number: 20

Abstract

Wearable flexible sensors for underwater communication and biomotion monitoring are gaining attention. However, developing gel-based strain sensors with high toughness, anti-swelling performance, robust underwater adhesion, and long-term stability remains challenging. Herein, we present a hydrophobic eutectogel (DPF-Zn@LNP-HEG) fabricated via the assembly of a polymerizable hydrophobic deep eutectic solvent (PHDES), 2-phenoxyethyl acrylate (PEA), and Zn2+-coordinated lignin nanoparticles (Zn@LNP). The resulting structure, composed of hydrophobic polymer networks and metal-phenolic complexes, forms hydrophobic microdomains that disrupt the hydration layer and prevent water penetration. Meanwhile, Zn@LNP serve as dynamic sacrificial cross-linkers, enhancing the material’s mechanical strength, energy dissipation, and anti-swelling properties. The resulting eutectogel exhibits remarkable tensile strength (1.14 MPa), superior toughness (3.15 MJ m−3), excellent anti-swelling properties (< 1% after 30 days), and robust underwater adhesion (1.07 MPa on glass). Based on these properties, we demonstrate an underwater strain sensor with high sensitivity (gauge factor = 8.12) and long-term stability, enabling underwater Morse code transmission, biomotion monitoring, and Bluetooth-based tracking of swimming movements. This work not only provides a versatile design paradigm for multifunctional underwater sensing platforms but also advances the high-value utilization of bio-based materials in next-generation flexible electronics.


Highlights:
1 A novel deep eutectic solvent with dual functions of hydrophobicity and polymerizability was developed.
2 Zn2+-coordinated lignin nanoparticles act as dynamic cross-linkers, significantly enhancing the toughness, energy dissipation, and swelling resistance of hydrophobic eutectogels.
3 Hydrophobic microdomains formed synergistically by polymer networks and metal-phenolic complexes disrupt the hydration layer on the gel surface, thereby preventing water penetration into the network.

Keywords

Lignin nanoparticles Hydrophobic deep eutectic solvents Underwater adhesion Underwater communication Biological motion detection
Lu, Fuyuan, Dan Sun, Wei He, Meng Li, Zhengjun Shi, Yiqiang Wu, Shao‑Fei Sun, Changyou Shao, and Runcang Sun. 2026. “Hydrophobic Eutectogels Reinforced by Zn2+-Coordinated Lignin Nanoparticles for Underwater Wearable Electronics”. Nano-Micro Letters 19 (August):20. https://doi.org/10.1007/s40820-026-02302-9.
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