碳基复合吸波材料研究进展分析

碳基材料由于具有优异的介电性能、良好的复合特性、特殊的微观结构、较低的密度、较强的化学稳定性以及使用便捷、维护简单等优点,在雷达吸波领域有着广阔的应用前景,已逐渐成为学界与工业界所追逐的热点研究对象与应用方向。本文在梳理总结分析国内外碳基材料雷达吸波应用研究成果的基础上,提出依据微观结构,按照形状维数划分归类,将材料分为零维(0D)、一维(1D)、二维(2D)和三维(3D)结构,进而以此为主线梳理碳基复合材料在雷达吸波隐身领域的研究进展,总结对比分析近年来国内外在碳基吸波材料方面的研究成果,指出未来材料将以"薄、轻、宽、强"为基础要求,朝着组成复合化、结构多样化、机理协同化和电磁参数可调化方向发展。     

碳基材料吸波性能研究进展

随着雷达探测技术的迅猛发展和电磁波辐射污染的日益加剧,新型吸波材料的研究和开发成为各国研究的热点。单一吸收剂存在吸波频带窄和吸收强度低等缺点,无法满足新型吸波材料频带宽、厚度薄、质量轻、吸收强的要求。碳材料具有密度低和吸波性能好等优点,通过与其他吸收剂的双组分、多组分复合,或对复合材料的微观结构进行设计,碳系复合材料表现出优异的吸波性能。简要介绍了吸波材料的工作机理,然后分别从炭黑、碳纤维、碳纳米管、石墨烯和其他碳系材料等5个方面综述了碳系材料在电磁波吸收中的应用和发展,归纳了碳系材料吸波性能的最新研究进展,最后提出了当前研究中存在的不足并明确了研究方向。     

In-Situ Fabrication of Sustainable-N-Doped-Carbon-Nanotube-Encapsulated CoNi Heterogenous Nanocomposites for High-Efficiency Electromagnetic Wave Absorption (Small 40/2023)

Developing carbon encapsulated magnetic composites with rational design of microstructure for achieving high-performance electromagnetic wave (EMW) absorption in a facile, sustainable, and energy-efficiency approach is highly demanded yet remains challenging. Here, a type of N-doped carbon nanotube (CNT) encapsulated CoNi alloy nanocomposites with diverse heterostructures are synthesized via the facile, sustainable autocatalytic pyrolysis of porous CoNi-layered double hydroxide/melamine. Specifically, the formation mechanism of the encapsulated structure and the effects of heterogenous microstructure and composition on the EMW absorption performance are ascertained. With the presence of melamine, CoNi alloy emerges its autocatalysis effect to generate N-doped CNTs, leading to unique heterostructure and high oxidation stability. The abundant heterogeneous interfaces induce strong interfacial polarization to EMWs and optimize impedance matching characteristic. Combined with the inherent high conductive and magnetic loss capabilities, the nanocomposites accomplish a high-efficiency EMW absorption performance even at a low filling ratio. The minimum reflection loss of −84.0 dB at the thickness of 3.2 mm and a maximum effective bandwidth of 4.3 GHz are obtained, comparable to the best EMW absorbers. Integrated with the facile, controllable, and sustainable preparation approach of the heterogenous nanocomposites, the work shows a great promise of the nanocarbon encapsulation protocol for achieving lightweight, high-performance EMW absorption materials.