Su Xiaogang, Wang Jun, Han Mengjie, Liu Yanan, Zhang Bin, Huo Siqi, Wu Qilei, Liu Yaqing, Xu He-Xiu
Key Laboratory of Functional Nanocomposites of Shanxi Province, School of Materials Science and Engineering, North University of China, Taiyuan 030051, China; Air and Missile Defense College, Air Force Engineering University, Xi'an 710051, China.
Key Laboratory of Functional Nanocomposites of Shanxi Province, School of Materials Science and Engineering, North University of China, Taiyuan 030051, China.
J Colloid Interface Sci. 2023 Dec 15;652(Pt A):780-788. doi: 10.1016/j.jcis.2023.08.113. Epub 2023 Aug 19.
Carbon materials were widely used as electromagnetic (EM) wave absorption due to their advantages of light weight, environmental resistance and high electrical conductivity. However, conventional means were typically available by combining carbon and other materials to achieve effective absorption. Herein, a novel strategy using pure carbon aerogel with oriented structure was reported to enhance the EM wave absorption by synergistically modulating the wave propagation path and carbonization degree. The aerogel contained proposed modified carbon nanofibers (MCNF) derived from bacterial cellulose (BC), and core-shell carbon nanofibers @ reduced oxide graphene (CNF@RGO). The oriented structure was induced by the temperature field, which manifests anisotropic EM constitutive parameters (ε ≠ ε) at different directions of incident wave. The carbonization degree was adjusted by varying the carbonization temperature. At the carbonization temperature of 700 °C, the maximum reflection loss and effective absorption bandwidth reached -53.94 dB and 7.14 GHz, respectively, enabling the aerogel to outperform its previous counterparts. To clarify the EM wave mode-of-action in conjunction, physical models of the aerogel were established in addition to finite element simulation and theoretical analysis. Notably, the aerogel with a density of 3.6 mg/cm featured ultra-light weight, superhydrophobicity, superior compressibility, and thermal insulation. Our work offers an efficient strategy for designing broadband and multifunctional EM wave absorption materials (EWAMs), promising great potentials in complex stealth equipment.
碳材料因其重量轻、耐环境性和高导电性等优点而被广泛用作电磁波吸收材料。然而，传统方法通常是通过将碳与其他材料结合来实现有效吸收。在此，报道了一种使用具有定向结构的纯碳气凝胶的新策略，通过协同调节波传播路径和碳化程度来增强电磁波吸收。该气凝胶包含源自细菌纤维素（BC）的改性碳纳米纤维（MCNF）以及核壳碳纳米纤维@还原氧化石墨烯（CNF@RGO）。定向结构由温度场诱导，这在入射波的不同方向上表现出各向异性的电磁本构参数（ε≠ε）。通过改变碳化温度来调节碳化程度。在700℃的碳化温度下，最大反射损耗和有效吸收带宽分别达到-53.94dB和7.14GHz，使该气凝胶优于其先前的同类产品。为了阐明电磁波的作用模式，除了有限元模拟和理论分析外，还建立了气凝胶的物理模型。值得注意的是，密度为3.6mg/cm的气凝胶具有超轻重量、超疏水性、优异的可压缩性和隔热性。我们的工作为设计宽带和多功能电磁波吸收材料（EWAMs）提供了一种有效策略，在复杂隐身设备中具有巨大潜力。
