Electromagnetic wave absorption properties of SiC@SiO2 nanoparticles fabricated by a catalyst-free precursor pyrolysis method

Broadband gap semiconductor silicon carbide (SiC) is regarded as a promising microwave absorber depending on its peculiar electrical and physicochemical characteristics. Herein, to explore a lightweight SiC-based microwave absorber with practical application potential as well as strong attenuation and broadband, SiC@SiO2 nanoparticles (SiC@SiO2 NPs) were successfully fabricated by a catalyst-free pyrolysis strategy using polycarbosilane (PCS) as precursor. According to systematic investigation results concerning the electromagnetic parameters, a reasonable synergistic mechanism integrated multiple reflections, Debye relaxation and interfacial polarization relaxation was proposed to demonstrate the superior microwave absorption performances of SiC@SiO2 NPs. The microwave absorption investigation exhibits that the corresponding minimal reflection loss (RL) of -45.53 dB with broad effective absorption bandwidth (EAB) of 5.52 GHz (12.48-18.0 GHz) almost covering the whole Ku-band can be achieved at the matching thickness of 1.85 mm, suggesting their superior dissipation capability. (c) 2020 Elsevier B.V. All rights reserved.