Tailorable microwave absorption properties of RGO/SiC/CNT nanocomposites with 3D hierarchical structure

In this study, a new composite ceramic consisting of chemical vapor infiltrated (CVI) silicon carbide (SiC) and catalyst-assisted chemical vapor deposited (CACVD) carbon nanotubes (CNTs) on three-dimensional(3D) laminated-structure of reduced graphene oxide (RGO) foam (RGO/SiC/CNT) with a small thickness, lightweight, and robust broadband absorption properties was produced. The dual heterogeneous nanointerfaces between the RGO layers and SiC nanograins, SiC, and CNT network, resulted in a significant increase in the dipole and interfacial polarisation. The composite ceramics with a CNT content of 1.27 wt% exhibit an effective absorption bandwidth (EAB) that covers the entire X-band (8.2–12.4 GHz) and a minimal reflection loss of −20 dB at 9.8 GHz for a thickness of 2.9 mm. Owing to the unique 3D multi-scale hierarchical porous structure, the material has a very low density (approximately 0.7 g cm−3). The results of this study present a promising and designable approach for the preparation of lightweight and high-performance ceramic-based electromagnetic wave (EMW) absorption materials.