Covalent interaction enhanced electromagnetic wave absorption in SiC/Co hybrid nanowires

Abstract

The interaction between components in hybrids is an indispensable factor in designing and fabricating composites with distinguished electromagnetic (EM) absorption performances. Herein, covalently bonded SiC/Co hybrid nanowires (NWs) have been fabricated, which present significantly enhanced EM absorption compared to a simple physical mixture of SiC and Co. The hybrids are characterized by transmission electron microscopy, X-ray diffraction, Raman spectroscopy, vector network analysis, and X-ray absorption near-edge spectroscopy at the Si K-edge, C K-edge, Co L_3,2-edge and O K-edge. Microstructure analysis indicates the formation of Si–O–Co bonds between SiC NWs and magnetic Co nanocrystals. Charge transfer takes place in the covalently bonded SiC/Co hybrid NWs. The induced synergistic coupling interaction in SiC/Co leads to an effective EM absorption band (RL < −10 dB) covering the frequency range of 10–16.6 GHz when the Co content is 25.1 wt% in the hybrid.