Ma Wenjun, Tang Chuanhao, He Peng, Wu Xiaohan, Cui Zhong-Kai, Lin Shaoliang, Liu Xiaoyun, Zhuang Qixin
Key Laboratory of Advanced Polymer Materials of Shanghai, School of Material Science and Engineering, East China University of Science and Technology, Shanghai 200237, P. R. China.
School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, P. R. China.
ACS Appl Mater Interfaces. 2022 Aug 3;14(30):34985-34996. doi: 10.1021/acsami.2c08077. Epub 2022 Jul 23.
The design and development of radar--infrared compatible stealth materials are challenging in the field of broadband absorption due to the contradiction of stealth requirements and mechanisms in different frequency bands. However, hollow structures show great promise for multispectral stealth because they can lengthen the attenuation path of electromagnetic waves (EMWs) for microwave absorption, interrupt the continuity of heat-transport channels, and lower the thermal conductivity to realize infrared stealth. Here, a new morphological fabrication strategy has been developed to efficiently prepare compatible stealth nanomaterials. In a specific hydrothermal process, the confined growth of flake α-FeO (f-FeO) outside of hollow mesoporous carbon spheres (HMCS) is achieved using NH·HO as a shape-controlled reagent. The introduction of f-FeO helps to lower infrared emissivity and improve high-frequency impedance matching, which depends on the stable dielectric property of the specific flake shape. Moreover, the size of f-FeO can be regulated by changing the constituent proportion in the hydrothermal suspension to obtain excellent performance. The minimum reflection loss (RL) of the HMCS@f-FeO-6 composite is -34.16 dB at 2.4 mm, and the effective absorption bandwidth (EAB) reaches 4.8 GHz. Furthermore, the lowest emissivities of the HMCS@f-FeO-6-20 wt %/polyetherimide (PEI) film in the 3-5 and 8-14 μm infrared wavebands are 0.212 and 0.508, respectively. These discoveries may pave the way for the development of radar-infrared compatible stealth materials from the perspective of microstructural design.
由于不同频段隐身要求和机制的矛盾，雷达-红外兼容隐身材料的设计与开发在宽带吸收领域具有挑战性。然而，空心结构在多光谱隐身方面显示出巨大潜力，因为它们可以延长电磁波（EMW）的衰减路径以实现微波吸收，中断热传输通道的连续性，并降低热导率以实现红外隐身。在此，已开发出一种新的形态制备策略来高效制备兼容隐身纳米材料。在特定的水热过程中，使用NH·HO作为形状控制试剂，在中空介孔碳球（HMCS）外部实现片状α-FeO（f-FeO）的受限生长。f-FeO的引入有助于降低红外发射率并改善高频阻抗匹配，这取决于特定片状形状的稳定介电性能。此外，可以通过改变水热悬浮液中的组成比例来调节f-FeO的尺寸，以获得优异的性能。HMCS@f-FeO-6复合材料在2.4 mm处的最小反射损耗（RL）为-34.16 dB，有效吸收带宽（EAB）达到4.8 GHz。此外，HMCS@f-FeO-6-20 wt%/聚醚酰亚胺（PEI）薄膜在3-5和8-14μm红外波段的最低发射率分别为0.212和0.508。这些发现可能从微观结构设计的角度为雷达-红外兼容隐身材料的开发铺平道路。
