Regulation of impedance matching feature and electronic structure of nitrogen-doped carbon nanotubes for high-performance electromagnetic wave absorption. (10th May 2022)

• Record Type: Journal Article
• Authors: Cao, Fenghui; Xu, Jia; Liu, Minjie; Yan, Feng; Ouyang, Qiuyun; Zhang, Xitian; Zhang, Xiaoli; Chen, Yujin
• Is Part Of: Journal of materials science & technology. Volume 108(2022)
• Page Start: 1
• Page End: 9
• Publication Date: 2022-05-10
• Subjects: FeNi alloy -- CNTs -- Silica -- Nitrogen doping -- Electromagnetic wave absorption; Metals -- Periodicals; Materials science -- Periodicals; Materials science; Metals; Periodicals; 620.1105
• DOI: 10.1016/j.jmst.2021.08.048
• Languages: English
• ISSNs: 1005-0302

Abstract

Highlights: SiO2 supported-NCNTs with encapsulated with FeNi nanoparticles were fabricated. The absorption bandwidth of the NCNTs is 4.32 GHz with a thickness of 1.6 mm. SiO2 can adjust the conductivity and impedance matching properties. The method can be extended to development of other high performance absorbers. Abstract: In this study, we developed a facile method to fabricate three-dimensional (3D) structures composed of FeNi alloy nanoparticles encapsulated in N-doped carbon nanotubes that grafted on the SiO2 spheres (Fe x Ni y @NCNT@SiO2 ) for electromagnetic wave (EMW) absorption. The experimental results suggest that the impedance matching characteristic can be tuned by the introduction of SiO2 spheres in the 3D structure. Density functional theory (DFT) calculations showed that the introduction of Ni improved the polarization and conductive losses of the Fe x Ni y @NCNT@SiO2 . As a result, the optimal 3D structure exhibits excellent EMW absorption property with a reflection loss and effective absorption bandwidth are -49.39 dB and 4.32 GHz, respectively, even though the matching thickness is only 1.6 mm, superior to most magnetic carbon-based composites. Thus, our current approach opens up an effective way to the development of low-cost, high-performance EMW absorbers.