Mesoporous vanadium nitride nanofiber@N-doped carbon with excellent microwave absorption and anti-corrosion

Complex service conditions often cause corrosion, rendering most microwave absorbers ineffective. Consequently, the development of bifunctional materials with exceptional properties in terms of both anti-corrosion and microwave absorption is of utmost importance. In this study, vanadium nitride nanofiber @ N-doped carbon (VN-F@NC) composite material with excellent microwave absorption and anti-corrosion was synthesized by combining V2O5 precursor fibers encapsulated in polydopamine with ammonia reduction nitriding process. The amorphous N-doped carbon nanolayer, residual O element, and porous structure of VN-F@NC contribute to impedance matching, interfacial polarization, as well as multiple reflections and scattering. As a result, VN-F@NC exhibits strong microwave absorption ability in multiple bands, with optimal reflection loss of − 40.0 dB, − 63.6 dB, and − 52.5 dB in the C, X, and Ku bands, respectively. Moreover, the encapsulation of VN nanofibers with the N-doped carbon nanolayers protects them from corrosion, thereby increasing the polarization resistance to 3.61 × 105 Ω·cm2 and reducing corrosion current to 9.00 × 10-8 A/cm2. Therefore, the encapsulation of vanadium nitride fibers with N-doped carbon nanolayer emerges as a viable approach in enhancing the microwave absorption capabilities as well as the resistance against corrosion of absorbers. [Display omitted]