High‐Efficiency Microwave Attenuation of Magnetic Carbon Nanoparticle‐Decorated Tubular Carbon Nanofibers Composites at an Ultralow Filling Content

Abstract

AbstractFaced with the formidable challenge to achieve a powerful absorption and broad bandwidth under a thin response thickness at a low filler content, tailoring the composition and microstructure of the absorbers is generally regarded as a potential method to tackle it. In the study, unprecedented tubular carbon nanofiber/Co/nanoporous carbon (TCNFs/Co/NPC) hybrids with rich holes are obtained by the direct thermal treatment of tubular polymer nanofibers/ZIF‐67 (TPNFs/ZIF‐67) precursor, which is fabricated by controllable anchor of ZIF‐67 nanocrystals on the surface of sulfonated TPNFs (TPNFs‐SO3H). The dielectric parameters of the resultant samples are reasonably monitored by adjustable TPNFs‐SO3H dosage and filling content. Benefiting from the dielectric‐magnetic compositions and unique heterogeneous and porous configurations, the boosted impedance matching and polarization relaxation are given. Hence, under an ultralow filling content of 8 wt%, a minimum reflection loss (RLmin) value of −54.1 dB corresponding to a matching thickness of 2 mm and an effective absorption bandwidth (EAB) of 6.2 GHz at 2.5 mm are exhibited at the TPNFs‐SO3H usage of 100 mg and carbonization temperature of 700 °C, respectively. This work provides an instructive guidance for constructing highly efficient absorbers with strong attenuation and wide frequency range at a low thickness.