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Updated: Jul 31, 2026
09:11
Alternating Magnetic Field-Responsive Hybrid Gelatin Microgels for Controlled Drug Release
Published on: February 13, 2016
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Multi-layer alternating structured alginate hydrogels featuring exceptional flexibility and electromagnetic shielding
Taian He1, Chuyang Liu1, Zhiwei Chen1
1School of Material Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, PR China.
Journal of Colloid and Interface Science
|June 15, 2025
Summary
This study developed a novel multi-layer hydrogel using carbon nanotubes (CNTs) and cobalt (Co) nanoparticles for superior electromagnetic interference (EMI) shielding. The material offers excellent flexibility and absorption, addressing pollution concerns in flexible electronic applications.
Area of Science:
- Materials Science
- Nanotechnology
- Polymer Science
Background:
- Flexible electronics demand advanced electromagnetic shielding materials with high flexibility and absorption.
- Existing conductive hydrogels often exhibit insufficient shielding performance and environmental concerns.
Purpose of the Study:
- To develop a novel hydrogel-based electromagnetic shielding material with enhanced flexibility and absorption.
- To investigate the synergistic effects of carbon nanotubes (CNTs) and cobalt (Co) nanoparticles in hydrogels for electromagnetic shielding.
Main Methods:
- Fabrication of a multi-layer hydrogel film incorporating CNTs and Co nanoparticles in an alternating pattern.
- Utilizing hydrogen bonds for mechanical reinforcement within the hydrogel structure.
- Characterization of electromagnetic shielding performance, mechanical flexibility, and absorption-reflection-reabsorption mechanisms.
Main Results:
- The Co-CNT hydrogel film demonstrated favorable dielectric and magnetic loss properties.
- A multi-layer structure enhanced electromagnetic wave dissipation through an "absorption-reflection-reabsorption" mechanism.
- The final CNT/Co-CNT multi-layer hydrogel achieved 41 dB shielding effectiveness at 0.7 mm thickness with >85% absorption/total shielding.
Conclusions:
- The developed CNT/Co-CNT multi-layer hydrogel offers superior electromagnetic shielding performance and mechanical flexibility compared to existing materials.
- This research presents a novel approach for creating intelligent flexible EMI shielding materials.
- Potential applications include wearable smart devices and military technology.
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