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Vol. 14 (2022)

Significantly Enhanced Electromagnetic Interference Shielding Performances of Epoxy Nanocomposites with Long-Range Aligned Lamellar Structures

https://doi.org/10.1007/s40820-022-00949-8
Lei Wang
Shaanxi Key Laboratory of Catalysis, School of Chemistry & Environment Science, Shaanxi University of Technology, Hanzhong 723001, People’s Republic of China
Zhonglei Ma
Shaanxi Key Laboratory of Macromolecular Science and Technology, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi’an 710072, People’s Republic of China
Hua Qiu
Shaanxi Key Laboratory of Macromolecular Science and Technology, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi’an 710072, People’s Republic of China
Yali Zhang
Shaanxi Key Laboratory of Macromolecular Science and Technology, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi’an 710072, People’s Republic of China
Ze Yu
Shaanxi Key Laboratory of Macromolecular Science and Technology, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi’an 710072, People’s Republic of China
Junwei Gu
Shaanxi Key Laboratory of Macromolecular Science and Technology, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi’an 710072, People’s Republic of China

Corresponding Author: Junwei Gu

gjw@nwpu.edu.cn

Nano-Micro Letters, Vol. 14 (2022), Article Number: 224

Abstract

High‑efficiency electromagnetic interference (EMI) shielding materials are of great importance for electronic equipment reliability, information security and human health. In this work, bidirectional aligned Ti3C2Tx@Fe3O4/CNF aerogels (BTFCA) were firstly assembled by bidirectional freezing and freeze-drying technique, and the BTFCA/epoxy nanocomposites with long-range aligned lamellar structures were then prepared by vacuum-assisted impregnation of epoxy resins. Benefitting from the successful construction of bidirectional aligned three-dimensional conductive networks and electromagnetic synergistic effect, when the mass fraction of Ti3C2Tx and Fe3O4 are 2.96 and 1.48 wt%, BTFCA/epoxy nanocomposites show outstanding EMI shielding effectiveness of 79 dB, about 10 times of that of blended Ti3C2Tx@Fe3O4/epoxy (8 dB) nanocomposites with the same loadings of Ti3C2Tx and Fe3O4. Meantime, the corresponding BTFCA/epoxy nanocomposites also present excellent thermal stability (Theat-resistance index of 198.7 °C) and mechanical properties (storage modulus of 9902.1 MPa, Young's modulus of 4.51 GPa and hardness of 0.34 GPa). Our fabricated BTFCA/epoxy nanocomposites would greatly expand the applications of MXene and epoxy resins in the fields of information security, aerospace and weapon manufacturing, etc.


Highlights:


1 Ti3C2Tx@Fe3O4/CNF aerogels (BTFCA)/epoxy electromagnetic interference (EMI) shielding nanocomposites with long-range aligned lamellar structures were prepared by bidirectional freezing, freeze-drying and vacuum-assisted impregnation of epoxy resins.
2 Successful construction of 3D long-range aligned lamellar structures and electromagnetic synergistic effect could significantly increase the EMI shielding effectiveness and reduce the secondary contamination.
3 BTFCA/epoxy EMI shielding nanocomposites possessed outstanding EMI shielding effectiveness of 79 dB, and also presented excellent thermal stabilities and mechanical properties.

Keywords

Electromagnetic interference shielding Epoxy nanocomposites Ti3C2Tx Fe3O4 Bidirectional aligned three-dimensional conductive networks
Wang, Lei, Zhonglei Ma, Hua Qiu, Yali Zhang, Ze Yu, and Junwei Gu. 2022. “Significantly Enhanced Electromagnetic Interference Shielding Performances of Epoxy Nanocomposites With Long-Range Aligned Lamellar Structures”. Nano-Micro Letters 14 (November):224. https://doi.org/10.1007/s40820-022-00949-8.
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