Work

Precursor-Derived Mo2C/SiC Composites with a Two-Dimensional Sheet Structure for Electromagnetic Wave Absorption

Year: 2025

Type: article

Abstract: Precursor-derived silicon carbide (SiC) ceramics have been widely used as absorbing materials, but the residual carbon sink produced by ceramicization limits their application under high-temperature and oxygen-containing conditions, such as the nozzle or jet vane of high-speed aircraft. In this paper, a novel molybdenum carbide/silicon carbide (Mo2C/SiC) microwave-absorbing ceramic with a two-dimensional sheet structure was obtained through the pyrolysis of polycarbosilane-coated molybdenum sulfide (PCS@MoS2). The results indicate that addition of an appropriate amount of MoS2 can react with the free carbon generated during the pyrolysis of PCS, thereby reducing the material’s carbon content and forming Mo2C. Concurrently, the layered structural characteristics of MoS2 are utilized to create a two-dimensional composite structure within the material, which enhances the material’s absorption vastly. The as-prepared Mo2C/SiC ceramics sintered at 1300 °C exhibit a minimum reflection loss (RLmin) of −46.49 dB at 8.96 GHz with a thickness of 2.6 mm. Additionally, the effective absorption bandwidth (EAB) of Mo2C/SiC spans the entire X-band (8–12 GHz) due to the combined effect of multiple loss mechanisms.

Source: Materials

DOI: 10.3390/ma18071573