Tuning dielectric and electromagnetic absorption properties of SiC fiber by in-situ grown polycrystalline carbon nanowires

Silicon carbide fiber (SiC_f) has a promising potential to develop structural electromagnetic wave (EMW) absorption materials. Tuning dielectric properties of SiC_f is necessary to obtain excellent EMW absorption performances, which is always realized by the introduction of extra dielectric loss phases. Herein, in-situ grown polycrystalline carbon nanowires (CNW) as novel dielectric fillers, possessing moderate conductivity as well as efficient loss ability, were used to improve the EMW absorption performance of SiC_f. When the content of CNW is suited, CNW can interconnect with each other and form a multiporous network on the surface of SiC_f. Such a unique network makes a great contribution to good impedance matching as well as strong conductivity loss and polarization loss, which endows SiC_f with an effective absorption broadband (EAB) of 4.14 GHz at a thickness of 3.0 mm, demonstrating superior EMW absorption performance than most previously reported SiC_f/carbon hybrids.