Novel SiBCN composite fibers with broadband and strong electromagnetic wave absorption performance.

The SiBCN composite fibers with strong electromagnetic wave (EMW) absorption performance were successfully prepared via polymer-derived ceramics (PDCs) and electrospinning methods at relatively lower preparation temperature. The results showed that the in-situ generated free carbon which existed in the matrix in the form of simple substance and was characterized by low crystallinity. The graphite carbon improved the dielectric loss and properties of SiBCN composite fibers. In particular for the SiBCN composite fibers pyrolyzed at 1300 °C, the in-situ generated nano β-SiC crystallization increased the EMW absorption performance significantly. The minimum reflection loss (RL min) of the SiBCN-3 reached − 54.91 dB at 2.35 mm and the effective absorption band (EAB, RL ≤ −10 dB) reached 4.72 GHz (13.28–18 GHz, 1.75 mm). Hence, the SiBCN fibers prepared at relatively lower temperature give good absorption performance and predict a broader application prospect in the field of EMW absorption materials. • SiBCN fibers with excellent EMW absorption performance were successfully prepared. • The in-situ generated free carbon improved the dielectric loss and properties of SiBCN fibers. • The minimum reflection loss (RL min) of SiBCN-3 reached − 54.91 dB at 2.35 mm. • The effective absorption band (EAB, RL ≤ −10 dB) of SiBCN-3 reached 4.72 GHz (13.28–18 GHz) at 1.75 mm. [ABSTRACT FROM AUTHOR]