Polymer self-assembly guided heterogeneous structure engineering towards high-performance low-frequency electromagnetic wave absorption

• Published in: Journal of colloid and interface science Vol. 650; no. Pt B; pp. 1434 - 1445
• Main Authors: Ban, Qingfu, Li, Luwei, Li, Yan, Liu, Huimin, Zheng, Yaochen, Qin, Yusheng, Zhang, Hongru, Kong, Jie
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 15.11.2023
• Subjects: absorption; carbon; electromagnetic radiation; Electromagnetic wave absorption; Heterogeneous structure; Low frequency; Magnetic-dielectric synergy; nanocomposites; nanoparticles; Polymer self-assembly; polymers; porous media; Electromagnetic wave absorption; Heterogeneous structure; Low frequency; Polymer self-assembly; Magnetic-dielectric synergy
• ISSN: 0021-9797; 1095-7103; 1095-7103
• DOI: 10.1016/j.jcis.2023.07.054

[Display omitted] •Hierarchical FeCo/Co@NC nanocomposites were prepared by polymer self-assembly guided fabrication strategy.•Interfaces generated from FeCo-Co, FeCo/Co-carbon and amorphous-graphitic carbon contribute to interfacial polarization.•Enhanced natural resonance plays a crucial role for low frequency electromagnetic wave absorption.•The optimal RLmin and maximum EAB are −59.61 dB at 5.4 GHz and 6.27 GHz at 11.84 GHz, respectively. Magnetic-dielectric synergy is currently regarded as among the most effective approaches to achieve low-frequency electromagnetic wave absorption (EMA). However, designing and fabricating EMA materials with tunable magnetic-dielectric balance towards high-performance low-frequency EMA remains challenging. Herein, a polymer self-assembly guided heterogeneous structure engineering strategy is proposed to fabricate hierarchical magnetic-dielectric nanocomposite. Polymer assemblies not only can be employed as intermediates to encapsulate metal-organic frameworks and load metal hydroxide, but also that they play a crucial role for the in-situ formation of polycrystalline FeCo/Co composite nanoparticles. As a result, the minimum reflection loss (RLmin) can reach −59.61 dB at 5.4 GHz (4.8 mm) with a 20 wt% filler loading, while the effective absorption bandwidth (EAB, RLmin ≤ −10 dB) is 2.16 GHz, exhibiting excellent low-frequency EMA performance. Systematic investigations demonstrate that hierarchical mesoporous carbon matrix that supports FeCo/Co composite nanoparticles is beneficial for optimizing impedance matching and increasing attenuation capacity. In general, this study opens up new prospects for developing magnetic-dielectric EMA materials using a polymer self-assembly guided heterogeneous structure engineering strategy, which may receive significant attention in future research.