Morphology-size synergy strategy of SiC@C nanoparticles towards lightweight and efficient microwave absorption

Abstract

Micro nanocomposites with multi-media components and rich heterogeneous interfaces have been proved to be the preferred electromagnetic functional bodies, especially in the field of electromagnetic wave absorption. The special composite structure of hollow, mesoporous and core–shell has excellent adjustable potential, it is also a high-quality route to expand electromagnetic characteristics. Herein, a synergistic strategy for sphere-line morphology evolution and particle size control of SiC/C composites by varying the calcination temperature and pH environment is proposed. The results show that the sample calcined at 1350 ℃ is hollow mesoporous [email protected] microsphere ([email protected]), it has the most excellent microwave absorption (MA) performance when the amount of ammonia is 3 ml, its effective absorption bandwidth (EAB) is 5.61 GHz at 2.1 mm, and the maximum reflection loss (RLmin) is −45.61 dB at 13.2 GHz. The excellent performance is due to the combination of good impedance matching and strong dielectric loss brought by semiconductor SiC/C composites. Multi-angle control strategy of hollow mesoporous [email protected] heterostructure and particle size can effectively adjust the electromagnetic parameters, which provides useful thinking for the design of other nano-scale dielectric composite materials.