1成果简介 构建多组分异质界面并可视化磁畴演变,已成为开发高性能电磁波衰减(EMWA)材料的关键研究方向。然而,设计具有此类界面的MXene-金属-碳复合材料仍面临重大挑战。本文,南昌航空大学彭玉辉、张月、刘崇波教授等在《Chemical Engineering Journal》期刊发表名为“Multi-component heterogeneous interface engineering and magnetic domain evolution for broadband electromagnetic wave attenuation”的论文,研究提出一种静电势场驱动的组装策略,用于合成片-球结构的MXene/Co@NC复合材料。异质界面的形成引发显著的极化松弛效应,而磁性颗粒的掺入则增强了材料的磁损耗能力。 由此,该MXene/Co@NC复合材料展现出卓越的EMWA性能,实现6.93 GHz的宽效用吸收带宽(EAB)。此外,基于计算机模拟技术的雷达截面积仿真验证了材料优异的雷达隐身特性。基于波导的有限元模型实现了电磁损耗的可视化呈现,微磁学模拟则阐明了磁性粒子诱导的磁损耗机制。相邻磁畴构成的耦合网络优化了阻抗匹配,强化了电磁衰减效果。本研究为多组分异质界面结构设计提供了新思路,深入揭示了磁畴动力学规律,为新一代磁性电磁波吸收材料的研发奠定了坚实基础。 2图文导读 
图 1. (a) Schematic illustration of the synthesis process of MXene/Co@NC composites. (b-g) SEM images of MCNC-1, 2, 3. (h) TEM image of MCNC-2. Element mapping images showing (e1) Ti, (e2) C, (e3) Co, and (e4) N. 
图2. Characterization of the samples: (a) XRD patterns, (b) Raman spectra, (c) Magnetic hysteresis loops at room temperature. (d) Full XPS survey spectrum. (e-i) High-resolution XPS spectra of Ti 2p, C 1 s, Co 2p, N 1 s, and O 1 s for the MCNC-2 composite. 
图3. (a-d) EM parameters of MXene and MNCN-1, 2, and 3. (e) Dielectric loss tangent, magnetic loss tangent, and R for all samples; (f-g) Cole–Cole plots of MCNC-1 and MCNC-2. (h-j) 3D RL–frequency–thickness mappings. (k-m) |Zin/Z0| 3D plots. (n-p) Smith charts for MCNC-1, 2, and 3. 
图4. Finite element simulation and electronic structure analysis of MXene/Co@NC composites. (a) Schematic of the waveguide model; (b-c) Simulated electric and magnetic field distributions. (d) DOS of MXene, Co@NC, MXene/Co@NC. (e) 3D charge density difference plot for MXene/Co@NC composites. (f-h) Electric field, magnetic field, and power-loss distributions of MCNC-2. (i) Schematic of the gradient metamaterial structure. (j) RL of the gradient structure. 
图5. (a) Magnetic domain evolution of a single cobalt nanoparticle under an alternating magnetic field; (b) 3D structural transition of a single cobalt particle from the initial to the transition state; (c) magnetic coupling network under external magnetic field stimulation. 
图6. (a-c) 3D radar scattering maps of MCNC-1, MCNC-2, and MCNC-3. (d) Schematic diagram of CST far-field simulation. (e) Simulated RCS curves for PEC and MCNC-1, 2, and 3. (f-h) Schematic illustrations of EM loss mechanisms. 3小结 综上所述,通过简便的静电势场驱动组装策略,成功合成了片层-球形MXene/Co@NC复合材料,实现了Co@NC与少层MXene纳米片的高效集成。金属、碳和MXene等多组分的引入形成了高密度的异质界面,显著增强了界面极化效应,进而提升了材料的电磁波吸收性能。实验结果表明:当Co@NC含量为25 mg时,优化后的MCNC-2复合材料在1.76 mm厚度下实现−47.74 dB最小反射损耗,1.8 mm厚度下呈现6.93 GHz宽带宽。有限元模拟进一步证实电磁波与材料相互作用时的衰减效应,彰显其卓越的波吸收能力。此外,通过引入合理设计的梯度超材料结构,有效扩展了电磁波吸收带宽,相较传统波吸收材料具有显著优势。互补的微磁模拟实现了磁畴演变的动态可视化,而磁耦合网络分析阐明了协同磁响应行为,证实了材料稳健的磁损耗特性。总体而言,本研究为多组分异质界面系统设计提供了宝贵启示,深化了对磁损耗机制的认知,为未来高性能电磁波吸收材料的研发开辟了前景广阔的策略路径。 文献: 
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