Multilevel structure carbon aerogels with 99.999 % electromagnetic wave absorptivity at 1.8 mm and efficient thermal stealth
Multilevel structure carbon aerogels with 99.999 % electromagnetic wave absorptivity at 1.8 mm and efficient thermal stealth
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DOI：
10.1016/j.cej.2022.139110
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发表时间：
2022-09-20
影响因子：
15.1
通讯作者：
Ji, Guangbin
中科院分区：
文献类型：
--
作者：
Chen, Xinting;Wang, Zhide;Ji, Guangbin
鉴于复杂的实际环境和应用领域，迫切需要将多种功能集成到一种材料中。基于纳米位点的引入，多层结构协同作用的创建，首次制备了一种轻量化的电磁波-红外隐身兼容复合材料。其中，多接触点和界面极大地限制了热传导，增强了协同极化。此外，低发射率的金纳米粒子不仅降低了外热辐射，而且提高了传导损耗。优化后的复合材料具有优异的热隐身性能和超高电磁波吸收性能。当目标温度为120℃时，表面温度与环境背景温度之差小于5℃，从而有效缩短红外系统对目标的探测距离。该产品的反射损耗最小为55.9 dB，厚度仅为1.8 mm，在1-5 mm范围内具有16 GHz的超宽有效吸收带宽。令人惊讶的是，在远场条件下，最小雷达截面值可以达到-49 dB m2。这项工作为合成具有优异EMA和热隐身性能的功能材料提供了有价值的见解。
Given the complex practical environment and application fields, it is urgent to integrate various functions into one material. Based on the introduction of nano-sites, the creation of multilevel structures synergy, a light weight electromagnetic wave-infrared stealth compatible composite was prepared for the first time. In which the multi -contact sites and interfaces greatly limited the thermal conduction and enhanced the synergistic polarization. Moreover, the gold nanoparticles with low emissivity not only reduced the external thermal radiation, but also promoted the conduction loss. Optimized composites showed excellent thermal stealth and ultra-high electro-magnetic wave absorption (EMA) performance. The difference between the surface and the ambient background temperature was less than 5 degrees C when the target temperature was 120 degrees C, thus the detection distance of the infrared system to the target would be effectively reduced. The products provided a minimum reflection loss of-55.9 dB with a thickness of only 1.8 mm, and an ultra-wide effective absorption bandwidth of 16 GHz within 1-5 mm. Surprisingly, in the far-field condition, the minimum radar cross section value can achieve-49 dB m2. This work provides valuable insights for synthesizing functional materials with excellent EMA and thermal stealth properties.