Adjustable iron‐containing SiBCN ceramics with high‐temperature microwave absorption and anti‐oxidation properties

Quaternary siliconboron carbonitride (SiBCN) ceramics show excellent high‐temperature stability and oxidation resistance, indicating great potential as high‐temperature electromagnetic (EM) wave absorbing materials. In this contribution, an efficient and facile method was developed to prepare bulk iron‐containing SiBCN (Fe–SiBCN) ceramics with remarkable EM wave absorption at high temperature by pyrolyzing boron and iron containing precursors (PSZV‐B–Fe). The introduction of boron and iron not only improves the high‐temperature stability but also influences the complex permittivity and EM wave absorption. The minimum reflection coefficient (RCmin) is −61.05 dB, and the effective bandwidth absorption (EAB) is 3.35 GHz (9.05–12.4 GHz). The RCmin will be decreased to −52.3 dB at 600°C as well as the EAB covers more than 67% of the X band (2.8 GHz). The high‐temperature stable Fe–SiBCN ceramics with adjustable dielectric properties can be utilized as high‐performance EM wave‐absorbing materials in high‐temperature and harsh environments. A high‐temperature stable and anti‐oxidized bulk iron‐containing SiBCN (Fe‐SiBCN) ceramics with remarkable EM wave absorption is prepared by pyrolyzing a boron and iron containing precursor. The minimum reflection coefficient (RCmin) can be as low as −61.05 dB, and the effective bandwidth absorption (EAB) is 3.35 GHz (9.05–12.4 GHz). RCmin still can be decreased to −52.3 dB as well as the EAB covers more than 67% of the X band even if at 600°C.