Zhao Pei-Yan, Wang Hui-Ya, Wang Guang-Sheng
School of Chemistry, Beihang University, Beijing, China.
Front Chem. 2020 Feb 28;8:97. doi: 10.3389/fchem.2020.00097. eCollection 2020.
In this manuscript, we constructed a Ni/MWCNTs absorber and properly adjusted the permittivity resulted from absorber content in the PVDF to optimize impedance matching properties. Both ε' and ε″ increase obviously with the increasing content of Ni/MWCNTs in PVDF, demonstrating that dielectric properties are dependent on the conductivity. Moderate dielectric properties and excellent impedance matching can be obtained for the filler content of 20 wt% Ni/MWCNTs. Reasonable impedance matching allows electromagnetic waves to propagate into the materials and finally realize energy dissipation through dielectric loss and interfacial polarization. As expected, the minimum reflection loss () of -46.85 dB at 6.56 GHz with a low filler loading (20 wt%) and wide effective bandwidth (<-10 dB) of 14.0 GHz in the thickness range of 1.5-5.0 mm was obtained for the commercial Ni/MWCNTs composites, which is promising for mass production in industrial applications. Our findings offer an effective and industrialized way to design high-performance material to facilitate the research in microwave absorption.
在本论文中，我们构建了一种镍/多壁碳纳米管吸收体，并适当调整了聚偏氟乙烯中吸收体含量所导致的介电常数，以优化阻抗匹配特性。随着聚偏氟乙烯中镍/多壁碳纳米管含量的增加，ε'和ε″均明显增大，这表明介电性能取决于电导率。对于20 wt%镍/多壁碳纳米管的填料含量，可获得适度的介电性能和优异的阻抗匹配。合理的阻抗匹配使电磁波能够传播到材料中，并最终通过介电损耗和界面极化实现能量耗散。正如预期的那样，商业化镍/多壁碳纳米管复合材料在1.5 - 5.0 mm的厚度范围内，在低填料负载量（20 wt%）下于6.56 GHz处获得了-46.85 dB的最小反射损耗（）以及14.0 GHz的宽有效带宽（<-10 dB），这对于工业应用中的大规模生产很有前景。我们的研究结果提供了一种有效且工业化的方法来设计高性能材料，以促进微波吸收方面的研究。
