Microwave induced in-situ formation of SiC nanowires on SiCNO ceramic aerogels with excellent electromagnetic wave absorption performance

Keke Yuan,Mingliang Li,Hailong Wang,Hongliang Xu,Biao Zhao,Daoyang Han,Junfang Liang,Wen Liu,Rui Zhang,Gang Shao,Hongxia Lu,Wanyu Zhao

doi:10.1007/s40145-021-0510-1

Abstract

Electromagnetic absorption (EMA) materials with light weight and harsh environmental robustness are highly desired and crucially important in the stealth of high-speed vehicles. However, meeting these two requirements is always a great challenge, which excluded the most attractive lightweight candidates, such as carbon-based materials. In this study, SiCnw-reinforced SiCNO (SiCnw/SiCNO) composite aerogels were fabricated through the in-situ growth of SiCnw in polymer-derived SiCNO ceramic aerogels by using catalyst-assisted microwave heating at ultra-low temperature and in short time. The phase composition, microstructure, and EMA property of the SiCnw/SiCNO composite aerogels were systematically investigated. The results indicated that the morphology and phase composition of SiCnw/SiCNO composite aerogels can be regulated easily by varying the microwave treatment temperature. The composite aerogels show excellent EMA property with minimum reflection loss of −23.9 dB@13.8 GHz, −26.5 dB@10.9 GHz, and −20.4 dB@14.5 GHz and the corresponding effective bandwidth of 5.2 GHz, 3.2 GHz, and 4.8 GHz at 2.0 mm thickness for microwave treatment at 600 °C, 800 °C, and 1000 °C, respectively, which is much better than that of SiCN ceramic aerogels. The superior EMA performance is mainly attributed to the improved impedance matching, multi-reflection, multi-interfacial polarization, and micro current caused by migration of hopping electrons.

Highlights

Tremendous efforts have been devoted to developing excellent electromagnetic absorption (EMA) materials for electronic safety and defense stealth technology [1,2]
Polymer-derived SiCN ceramics (PDC-SiCN) possess excellent thermal mechanical property and oxidation/ corrosion resistance [9,10,11], and owing to their easilytunable microstructure and composition [12], especially the carbon dangling-bonds in SiCN matrix [13,14], the EMA property of PDC-SiCN is excellent, such as SiCN [15] and SiBCN/graphene@Fe3O4 [16]
After ferrocene-modified PDC-SiCN aerogels were heat treated using microwave heating technology at 600 °C, some short whiskers wrapped on the surfaces of SiCN ceramic matrix were observed (Fig. 1(b))

Summary

Introduction

Tremendous efforts have been devoted to developing excellent electromagnetic absorption (EMA) materials for electronic safety and defense stealth technology [1,2]. The effects of microwave-treated temperature on microstructure evolution, dielectric and EMA properties of SiCnw/SiCNO composite aerogels were investigated.

Results

Conclusion