All-Ceramic SiC Aerogel for Wide Temperature Range Electromagnetic Wave Attenuation

Area of Science:

• Materials Science
• Nanotechnology
• Electromagnetism

Background:

• Development of advanced materials for electromagnetic (EM) wave attenuation is crucial.
• Silicon carbide (SiC) based materials offer potential due to their inherent properties.
• Graphene oxide (GO) can be used to tune material characteristics.

Purpose of the Study:

• To fabricate and characterize novel all-ceramic SiC aerogels doped with GO.
• To investigate the influence of GO concentration on the aerogels' morphology and EM performance.
• To evaluate the potential of these SiC aerogels as EM attenuation materials.

Main Methods:

• Fabrication of SiC aerogels using freeze casting and carbothermal reduction of GO-doped SiC nanowire suspensions.
• Investigation of varying GO concentrations (0, 1, 2, 4 mg/mL).
• Characterization of porous morphology, chemical composition, and electromagnetic (EM) shielding effectiveness.

Main Results:

• The optimal SiC aerogel achieved over 90% X-band attenuation at a 3.3 mm thickness.
• The material exhibited an ultralight density of 0.2 g/cm³ and low thermal conductivity (0.05 W/mK).
• High thermal stability was confirmed, with material composition remaining stable up to 800 °C.

Conclusions:

• The developed all-ceramic SiC aerogels possess excellent lightweight, thermal stability, and EM attenuation properties.
• The material's performance is optimized by GO doping.
• These SiC aerogels are promising candidates for EM attenuation in harsh environments.