N-Doped Carbon Fibers with Embedded ZnFe and Fe3C Nanoparticles for Microwave Absorption

Microwave absorbing materials (MAMs) play a vital role in the field of electromagnetic wave pollution protection. Herein, multiple interfacial ZnFe/Fe3C@C porous nanofibers as a microwave absorber were prepared by electrospinning and subsequent thermal treatment. The elaborately designed ingredients and porous feature of the structure introduce good impedance matching. The multiple interfacial heterojunction structure and the self-doping of nitrogen atoms of the proposed carbon-based magnetic fibers promote dielectric polarization relaxation. Moreover, the attenuation capacity and impedance matching can be adjusted by the carbothermal temperature. The obtained composites exhibit excellent microwave absorption performance, which possess a minimum reflection loss of −33.57 dB at 13.92 GHz and an effective absorption bandwidth (RL < −10 dB) of 4.16 GHz. These favorable characteristics and excellent performance of ZnFe/Fe3C@C porous nanofibers can promote the development of an efficient, lightweight microwave absorber.