Hollow SiC foam with a double interconnected network for superior microwave absorption ability

For high-efficiency microwave absorber, it is wise to integrate the porous structure and SiC material. In this work, the hollow SiC foam with a double interconnected network is proposed via a simple chemical vapor deposition and direct oxidation process. The SiC film imparts the foam with excellent mechanical property and microwave absorption performance. As a result, the fabricated SiC foam possesses a superior compressive response of 14.09 MPa at 17.51% strain, which is much higher than the original C foam or SiC reinforced C foam. Besides, SiC foam shows a minimum reflection loss value of −50.75 dB at 4.85 mm at 6.00 GHz. The effective bandwidth frequency and electromagnetic absorption efficiency also prove the superiority of the hollow porous architecture at the specified thickness, followed by a simple interpretation of the microwave absorbing mechanism. Given the excellent characteristics, the SiC foam has the enormous applied potential as a lightweight absorber in complex microwave absorbing conditions, especially for high temperature applications.