Novel and efficient electromagnetic wave absorption of SiBCN(Fe) nanofibers

In this work, novel and efficient SiBCN(Fe) nanofibers were successfully prepared by electrostatic spinning and polymer-derived ceramic (PDCs) methods, and their electromagnetic wave (EMW) absorption properties were investigated after pyrolysis at 1100–1500 °C. Notably, SiBCN(Fe) nanofibers exhibit the best EMW absorption performance after pyrolysis at 1400 °C, with a minimum reflection loss (RLmin) of −72.87 dB at 3.6 GHz and an effective absorption bandwidth (EAB, RL≤ −10 dB) of 4.34 GHz at 1.44 mm. Its excellent EMW absorption performance is attributed to its fiber structure, which facilitates the multi-level reflection and scattering of EMW. Meanwhile, the doping of Fe facilitates the in-situ generation of substances such as Fe3Si, which can impart SiBCN(Fe) nanofibers with magnetic loss and perfect impedance matching performance. The simulated radar cross-section (RCS) results show that the optimized SiBCN(Fe) nanofibers can effectively achieve the attenuation of EMW in a practical environment. Compared with many previously reported magnetic hybrid composites, SiBCN(Fe) nanofibers exhibit excellent electromagnetic absorption properties with a simpler preparation process, which have the potential to be used as lightweight, ultra-strong radar-absorbing materials.