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. • In-situ Mo-B doped carbon nanofibers with exceptional electromagnetic properties via electrospinning and pyrolysis. • Record 32.1 GHz bandwidth (93% of 2-40 GHz) with -57.7 dB reflection loss through multiscale design. • UAV coatings demonstrate >16.42 dB·m² RCS reduction at 11 GHz across 70°-110°, outperforming metal-backed systems.