Enhanced microwave absorption in C@Co/carbonyl iron fiber composite with multi-level interfaces

With the accelerated advancement of electronic information and military technology, there is a pressing need to develop high-performance absorbing materials. In this paper, we proposed to enhance the microwave absorption performance according to the coupling effect of electric–magnetic loss in magnetic composites with multi-level interfaces. Specifically, the magnetic cobalt nanoparticles were embedded within the porous carbon matrix derived from a metal–organic framework and composited with carbonyl iron fiber to prepare C@Co/CIF composites with multi-level interfaces. When the C@Co/CIF loading ratio was 30 wt%, the minimum reflection loss (RL min ) of the absorber was − 45.65 dB, and the effective absorption bandwidth was about 4.8 GHz with a matching thickness of 1.35 mm, which presented a good microwave absorption performance. Electromagnetic waves can penetrate through multiple scattering and internal reflections and eventually disappear through multi-level interfaces of C@Co/CIF composites. Meanwhile, the dielectric porous carbon, the magnetic cobalt, and CIF made a synergistic effect on the electric–magnetic loss, which was responsible for the attenuation of the electromagnetic wave. The findings of this study offer insight that can inform the design and fabrication of metal–organic framework derivatives for electromagnetic wave absorption materials.