Biomass carbon-derived SiC nanowires for efficient electromagnetic wave absorption

SiC nanowires (SiC NWs) as one-dimensional nanomaterials, offer a high aspect ratio, good thermal stability, and promising EMW absorption capabilities, making them suitable for high-temperature EMW absorption applications. However, the high production cost of SiC NWs presents a significant barrier to large-scale manufacturing. To address this issue, this study proposes a novel strategy using low-cost biomass flour as the carbon source and neutral silica sol as the silicon source to synthesize SiC NWs with high yield and favorable morphology via chemical vapor deposition (CVD). Thermogravimetric analysis revealed an oxidation temperature of 925 °C for the SiC NWs, confirming their excellent thermal stability. Furthermore, as-prepared SiC NWs also exhibited outstanding EMW absorption properties, including a minimum reflection loss (RL_min) of −45.21 dB and a maximum effective absorption bandwidth (EAB_max) of 4.8 GHz. The practical EMW attenuation performance of the SiC NWs was evaluated using radar cross-section (RCS) simulation, which showed the highest RCS reduction of 48.11 dB m² at an incident angle of θ = 33°. These results indicate that the successful preparation of SiC NWs provides a strong foundation for their application as high-level EMW absorbing materials.