Enhanced electromagnetic wave absorption of multicore Fe4N@N-doped porous carbon core-shell microspheres through dielectric-magnetic coordination

With the vigorous development of nanotechnology, precise control of composition and structure in carbon-coated magnetic core-shell materials for efficient electromagnetic wave absorption is an attractive research direction. In this work, multi-core Fe₄N@N-doped porous carbon core-shell microspheres (p-FCNS) were successfully synthesized using a controllable method to achieve excellent electromagnetic wave absorption performance at a thin matching thickness. p-FCNS offered multiple advantages due to the transformation of the Fe₄N phase and porous carbon matrix: (I) excellent magnetic loss and charge conduction ability; (II) optimized impedance matching; and (III) enhanced interfacial polarization and other attenuation mechanisms. Through the synergistic effect of magnetic-dielectric loss, p-FCNS realized a minimum reflection loss of −57.61 dB (at 1.74 mm) and an optimal absorption bandwidth of 5.27 GHz (at 1.68 mm). Therefore, this work substantiated the significant potential of Fe₄N@porous carbon composites for the application of electromagnetic wave absorption, and provided novel insights into the composition and structure control of high-performance electromagnetic wave absorption materials.