Grow defect-rich bamboo-like carbon nanotubes on carbon black for enhanced microwave absorption properties in X band

Due to the limited electromagnetic wave (EMW) loss capacity and agglomeration, carbon black (CB) grad-ually fails to meet the increasingly harsh demanding conditions. Herein, defect-rich bamboo-like carbon nanotubes (CNTs) were grown on CB by the process of chemical vapor deposition. CNTs prepared in situ on CB can assist it to build a developed multilevel conductive network and introduce plentiful CB/CNTs nano-interfaces. What's more, the defects that accompany the growth of CNTs endow CNTs with a moder-ate conductivity and good impedance matching, thereby causing an effective microwave absorption (MA). Meanwhile, the high-density defects on CNTs can induce dipole polarization to further strengthen the EMW loss ability. The influence of CNTs with different growth time on MA performance has been ex-plored. Profiting from the structural merits, the synthesized CB-CNT with CNTs growth time of 40 min exhibits the optimal absorbing property, which has the minimum reflection loss of-53.6 dB and maxi-mum effective absorption bandwidth of 4.1 GHz with the thickness of 2.7 mm, covering almost the entire X band. The introduction of defect-rich CNTs significantly enhances the EMW loss ability of CB, which provides a rational strategy for the design of high-efficient microwave absorption materials. (c) 2022 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.