Super Tough Multifunctional MXene/PAA-CS Double Network Hydrogels with High Mechanical Sensing Properties and Excellent EMI Shielding Performance

Lin Mei; Wenchong Ouyang; Limin Xu; Yuanlong Huang; Qi Liu; Yu Bai; Quanming Lu; Tianzhi Luo; Zhengwei Wu

doi:10.1002/smll.202410687

Super Tough Multifunctional MXene/PAA-CS Double Network Hydrogels with High Mechanical Sensing Properties and Excellent EMI Shielding Performance

Small. 2024 Dec 26:e2410687. doi: 10.1002/smll.202410687. Online ahead of print.

Authors

Lin Mei^{1

2}, Wenchong Ouyang^{3

4}, Limin Xu⁵, Yuanlong Huang⁵, Qi Liu⁶, Yu Bai⁷, Quanming Lu³, Tianzhi Luo^{2

8}, Zhengwei Wu^{1

4}

Affiliations

¹ School of Nuclear Science and Technology, University of Science and Technology of China, Hefei, 230026, China.
² CAS Key Laboratory of Mechanical Behavior and Design of Materials, Department of Modern Mechanics, University of Science and Technology of China, Hefei, 230026, China.
³ Deep Space Exploration Laboratory, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, 230026, China.
⁴ Joint Laboratory of Plasma Application Technology, Institute of Advanced Technology, University of Science and Technology of China, Hefei, 230031, China.
⁵ Advanced Institute of Photonics Technology, School of Information Engineering, Guangdong University of Technology, Guangzhou, 510006, China.
⁶ School of Engineering, Yunnan University, Kunming, 650091, China.
⁷ Experimental Center of Engineering and Materials Sciences, University of Science and Technology of China, Hefei, 230026, China.
⁸ State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei, 230026, China.

PMID: 39723729
DOI: 10.1002/smll.202410687

Abstract

Hydrogels present significant potential in flexible materials designed for electromagnetic interference (EMI) shielding, attributed to their soft, stretchable mechanical properties and water-rich porous structures. Unfortunately, EMI shielding hydrogels commonly suffer from low mechanical properties, deficient fracture energy, and low strength, which limit the serviceability of these materials in complex mechanical environments. In this study, the double network strategy is successfully utilized along with the Hofmeister effect to create MXene/PAA (polyacrylic acid)-CS (chitosan) hydrogels and further strengthen and toughen the gel with (NH₄)₂SO₄ solution. The gel exhibits enhanced functionalities such as outstanding stretchability, excellent strain sensitivity (11.66), and super fracture energy (≥9 kJ m^-2). Notably, it demonstrates outstanding shielding effectiveness of 73.8 dB in the terahertz (THz) range, and the shielding properties can be effectively tuned by varying the MXene content, the (NH₄)₂SO₄ concentration, and the thickness of the hydrogel. Additionally, the gel shows robust and superior shielding effectiveness after repeated stretching and long-term dehydration. The MXene/PAA-CS double-network (DN) hydrogels would be an excellent candidate for EMI shielding materials in advanced flexible electronic equipment and soft robots.

Keywords: MXene; electromagnetic interference (EMI) shielding; fracture energy; hydrogel; strain sensing.

Abstract

Grants and funding