Atomically dispersed Fe-Co in electrospun SiC fiber matrix for enhanced electromagnetic wave absorption and desirable thermal stability

Abstract

The aerospace industry urgently demands high-performance electromagnetic wave absorbing materials that maintain stability under extreme temperatures. In this work, Fe-Co co-doped SiC nanofibers were developed via precision electrospinning and controlled pyrolysis. An atomic-scale dispersion of Fe and Co was achieved through a metal-polymer coordination strategy. These dopants function as active sites that promote phase nucleation, while also serving as electron donors to enhance polarization loss. Subsequent tuning of doping concentration enables synergy among conductive loss, polarization loss and magnetic loss. The optimized nanofiber exhibits outstanding performance, demonstrating an RLmin of −58.49 dB at 14.88 GHz with a 1.25 mm thickness, as well as a maximum EAB of 4.77 GHz. Remarkably, the material also demonstrates desirable thermal stability in argon atmospheres up to 1200 °C, even after oxidation at 800 °C for 30 min, it retains an RLmin of −26.35 dB and EAB of 3.04 GHz. This work establishes a new paradigm in doping-induced phase engineering, providing transformative strategy for developing next-generation extreme-environment electromagnetic wave absorbers.