Flexible Mo2C-Modified SiC/C Nanofibers for BroadBand Electromagnetic Wave Absorption

Materials with 1D structure exhibit a remarkable advantage for losing electromagnetic (EM) wave energy. Herein, flexible Mo 2 C-modified SiC/C nanofibers (Mo-SiC/C NFs) are synthesized for the first time by co-electrospinning and subsequent high-temperature pyrolysis, using polycarbosilane (PCS) and molybdenum acetyl acetone (MoO 2 (acac) 2 ) as precursors. It is found that the polymer derived temperature of PCS is significantly decreased by introducing MoO 2 (acac) 2 , as well as endowing the SiC/C NFs with good flexibility, high crystallinity, and remarkable microwave absorption performance. The as-prepared fibers dispersed in paraffin with a low filler loading (15 wt%) exhibit a minimum reflection loss (RL, dB) of -62.5 dB, and a wide effective absorption bandwidth (EAB, RL<-10 dB) of 6.8 GHz at 2.75 mm. Meanwhile, the EAB of the hybrid can cover the whole X-band and most of the C-band by modulating its thickness. These high-efficient performances mainly originate from the specific 1D microstructure, abundant interfaces and defects, and synergistic effect among SiC, Mo 2 C, and C matrix. Thus, this work offers a way to explore flexible SiC/C NFs as a promising candidate with lightweight and wide EAB for EM wave absorption.