Preparation and 3D network structure optimization of SiC and SiC@Fe₃Si nanofibers for enhanced electromagnetic wave absorption

The Electromagnetic wave absorbing materials (EWAM) prepared by coupling magnetic elements with SiC nanofibers have excellent comprehensive characteristics, including ample network free spaces, numerous interfacial polarization sites and enhanced dielectric dissipation capacity, exhibiting critical potential for 5G communication systems and artificial intelligence applications. Based on the design of three-dimensional (3D) network structure, nanofiber precursors were prepared by electrostatic spinning, and then SiC nanofibers and SiC@Fe₃Si composite nanofibers were synthesized by combination with carbothermal reduction reaction. The effective absorption bandwidth of SiC nanofibers reaches up to 6.16 GHz and the minimum reflection loss (RL_min) is −66.07 dB. After the introduction of magnetic components, the RL_min of SiC@Fe₃Si composite nanofibers (SC3-F) is increased to −73.75 dB. Scanning electron microscopy and electromagnetic parameters demonstrate the synergistic mechanism of interfacial/dipole polarization and magnetic coupling, revealing its important contribution to multiple reflections and impedance matching. In addition, further theoretical evaluations of the different domains were carried out through CST analog simulations, illustrating the effect of the materials on radar stealth. This study provides new ideas for the design of new-generation high-performance EWAM materials and lays the foundation for their extensive development in multifunctional applications.