Synergistic microwave attenuation via interface-engineered CoSi/SiC/Carbon nanofibers with multiphase coupling mechanisms

Lightweight CoSi/SiC/C hybrid nanofibers were fabricated via electrospinning followed by controlled pyrolysis. The pyrolysis temperature strongly influenced the microstructure and electromagnetic properties. The sample obtained at 1500 °C exhibited optimal performance, delivering a minimum reflection loss of −63.15 dB and an effective absorption bandwidth of 4.8 GHz at a thickness of only 1.5 mm. Structural analysis confirmed the formation of abundant heterogeneous interfaces (CoSi/SiC, C/SiC, and SiO x C y /C) and a graphitized carbon network, which synergistically enhanced interfacial polarization and conduction loss. Density functional theory calculations revealed interfacial charge transfer between CoSi and SiC, while radar cross-section simulations verified excellent stealth capability, with average RCS values below −12 dB m 2 at 10 and 12 GHz. These results demonstrate that interface-engineered CoSi/SiC/C nanofibers combine thin thickness, low filler content, and strong microwave absorption, highlighting their promise for next-generation electromagnetic wave absorbing and stealth materials.