Fabrication of C-doped SiC nanocomposites with tailoring dielectric properties for the enhanced electromagnetic wave absorption

Microwave absorbing materials with lightweight, strong absorption, broad bandwidth and thin matching thickness have gained considerable attentions in recent years. Herein, C-doped SiC ceramic nanocomposites with heterostructure were successfully fabricated via solvothermal method using renewable glucose as the carbon source. Such nanocomposites show different permittivity dependent on glucose contents. By tailoring the dielectric properties of the nanocomposites, the C-doped SiC nanocomposites using 0.50 mmol/mL glucose solution with a strong reflection loss of −76.6 dB at 16.0 GHz with the thickness of 1.66 mm were obtained. Microwave absorption mechanism indicates that dielectric loss originating from the conductive paths and dipole polarization contributes to the improvement microwave absorption properties. The results provide new strategy for designing and fabricating composites consisting of ceramic and C materials with the strong absorbing and broad bandwidth properties.