Impedance amelioration of coaxial-electrospun TiO2@Fe/C@TiO2 vesicular carbon microtubes with dielectric-magnetic synergy toward highly efficient microwave absorption
Impedance amelioration of coaxial-electrospun TiO2@Fe/C@TiO2 vesicular carbon microtubes with dielectric-magnetic synergy toward highly efficient microwave absorption
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DOI：
10.1016/j.cej.2021.133640
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发表时间：
2022-02-07
影响因子：
15.1
通讯作者：
Che, Renchao
中科院分区：
文献类型：
--
作者：
Jin, Chen;Wu, Zhengchen;Che, Renchao
阻抗匹配（Z）是高效吸波材料的一个关键问题，也是目前吸波材料研究的一大难题。碳基吸波材料由于缺乏磁损耗能力和电磁阻抗平衡，其微波衰减能力亟待提高。本文采用同轴静电纺丝技术成功构建了TiO2@Fe/C@TiO2多孔碳微管。通过引入空穴、磁性Fe颗粒和介质TiO 2涂层，特性阻抗逐渐得到改善。该复合材料实现了增强的微波性能，最大反射损耗高达-60.98 dB，在仅2.0 mm的厚度下具有4.8 GHz的宽吸收带宽。这种高度集成的具有管状多孔结构的多级泡状碳微管赋予组装体高磁各向异性和多界面，进一步提供复合材料：i）微米尺度一维各向异性磁耦合和电荷传导的双重网络，ii）四元组分的介电-磁协同作用，iii）渐进匹配的阻抗，通过微磁学模拟和电子全息证实。这一发现对高性能微波吸收剂的阻抗匹配控制具有重要意义。
Impedance matching (Z) is a key issue requested by high-efficient microwave absorption materials, which re-mains a major challenge. Lacking magnetic loss capacity and electromagnetic impedance balance, the microwave attenuation capacity of carbon-based absorbers urgently needs to be improved. Herein, a TiO2@Fe/C@TiO2 vesicular carbon microtube was reasonably constructed by coaxial electrospinning. The characteristic impedance was gradually improved by introducing cavities, magnetic Fe particles and dielectric TiO2 coating. The composite achieves an enhanced microwave performance with a maximum reflection loss of as strong as -60.98 dB and a broad absorption bandwidth of 4.8 GHz at only 2.0 mm thickness. Such a well-integrated hierarchically vesicular carbon microtube with a tubular porous structure endows the assembly with high magnetic anisotropy and multiple interfaces, further offers the composites: i) the dual-networks of micron-scale 1D anisotropic magnetic coupling and charge conduction, ii) dielectric-magnetic synergy of quaternary components, iii) progressively matched impedance, proved by micromagnetic simulation and electron holography. This finding might have great significance in the impedance matching control of high-performance microwave absorbents.