YbSiOC ceramics with a multidimensional nanostructure for high-efficiency electromagnetic wave absorption

The controllable microstructure of a material plays a vital role in its electromagnetic (EM) wave absorption performance. Herein, a multidimensional nanostructure including a matchstick-like SiCnws network structure with a carbon nanocluster was grown in-situ in a porous Yb₂Si₂O₇ ceramic by precursor infiltration and pyrolysis (PIP) to prepare YbSiOC ceramics. As the number of PIPs increased, the absorber (SiCnws and carbon) content increased to construct a multidimensional nanostructure, which also promoted conductivity loss, interfacial polarization loss and dipole polarization loss. The results showed that the YbSiOC ceramics (with an absorber content of 28.2 wt%) achieved a minimum reflection loss (RL_min) of − 50.0 dB at 9.39 GHz with 2.7 mm, and the effective absorption bandwidth (EAB) reached 4.2 GHz (in the X band) as the thickness increased from 2.1 to 3.5 mm. To conclude, the matchstick-like SiCnws and carbon nanoclusters build a multidimensional network structure that is capable of multiple reflections and scattering of EM waves in YbSiOC ceramics. This work proposes a feasible method to design rare earth silicates with EM absorbing performance, and it is expected to have durable applications in water-vapor environments.