In-situ Synthesis of Mo-B Co-Doped Carbon Nanofibers for Enhanced Microwave Absorption and Radar Stealth Applications

Distinguished by a unique three-dimensional (3D) network structure and commendable electrical conductivity, one-dimensional (1D) carbon nanofibers (CNF) exemplifies a pivotal class of microwave absorption materials. However, their effective absorption bandwidth (EAB) suffers from inadequacy on account of poor impedance matching. To conquer this drawback, a novel in situ dual-doping strategy was employed in this article. Incorporating boron (B) and low-valence-state molybdenum (Mo), this strategy is merged with electrospinning and high-temperature treatment, aimed to fabricate Mo and B co-doped carbon nanofibers (Mo-B/CNF) with superior microwave absorption performance. An array of characterization techniques were leveraged to delve into the microstructure and properties of the Mo-B/CNF. The analysis corroborated a uniform distribution of Mo and B elements within the carbon matrix, alongside the formation of Mo 2 N species. Outstanding microwave absorption was identified for the resulting Mo-B/CNF, accompanied by a minimum reflection loss of -57.7   dB at 10.3   GHz and an EAB of 6.05   GHz. As further demonstrated by radar cross-section simulations, the Mo-B/CNF is capable of attenuating electromagnetic scattering from metallic backplanes and large unmanned aerial vehicles, which highlights their promise in radar stealth applications. Following a structural optimization via 3D electromagnetic simulation software, the metamaterial fabricated from Mo-B/CNF attains an ultra-broad effective absorption bandwidth (EAB) of 32.1   GHz across the 2-40   GHz frequency range. This study delineates the electromagnetic wave absorption traits of Mo-B/CNF, and provides another insight for designing next-generation microwave absorption materials.