Microwave Absorption Performance of SiC/ZrC/SiZrOC Hybrid Nanofibers with Enhanced High-Temperature Oxidation Resistance

In carbide ceramics, ZrC has a high melting point, high hardness, and excellent thermal conductivity and electrical conductivity. It can be used as a suitable additive phase for SiC nanomaterials to enhance its high-temperature resistance to oxidation and its microwave absorption property. In our work, heterogeneous SiC/ZrC/SiZrOC hybrid nanofibers with different ZrC contents are prepared using polycarbosilane and zirconium acetylacetonate as raw materials through electrospinning and high-temperature pyrolysis processes. With an increase in the ZrC content from 0 to 10 wt %, the electrical conductivity of the hybrid nanofibers increases from 0.3448 to 2.5676 S/cm, and the average diameter decreases from 800 to 200 nm. The SiC/ZrC/SiZrOC hybrid nanofibers result in improved microwave-absorbing capability with a minimum reflection loss of about -40.38 dB at 14.1 GHz, a thickness of 4 mm, and antioxidant properties at 600 °C. These results prove that the heterogeneous SiC/ZrC/SiZrOC hybrid nanofibers have reasonable electrical conductivity. This results in dielectric loss, which is mainly because of the added ZrC. The dipole polarization, interfacial polarization, quarter-wave cancellation, and conductivity loss are the main reasons for the enhanced microwave absorption.