MIL-88B (Fe) driven Fe/Fe<sub>3</sub>C encapsulated in high-crystalline carbon for high-efficient microwave absorption and electromagnetic interference shielding
Xianfeng Yang, You Zhou, Hongna Xing, Hongpeng Wang, Wei Feng, Juan Feng, Xiuhong Zhu, Zhenhua Shi, Yan Zong, Xinghua Li, Xinliang Zheng
Abstract
Abstract Dual-functional magnetic/dielectric Fe/Fe 3 C@C composites were fabricated by pyrolysis of MIL-88B (Fe) in an Ar atmosphere, which was used for microwave absorption and electromagnetic interference (EMI) shielding. The Fe/Fe 3 C nanocrystals were completely encapsulated in crystalline carbon, which can improve oxidation resistance capacity. Owing to remarkable impedance matching and strong attenuation constants, the Fe/Fe 3 C@C composites show an optimal reflection loss (RL) value of −56.4 dB at 14.0 GHz and a broad effective absorption bandwidth (RL ⩽ −10 dB) of 4.8 GHz when the filling ratio and absorber thickness are only 20 wt% and 1.9 mm, respectively. Resulting from the high conductivity of crystalline carbon, magnetic loss of Fe/Fe 3 C, and core–shell structure, the Fe/Fe 3 C@C composites also show remarkable EMI shielding properties at the X band, which are enhanced by increasing the filling ratio of the Fe/Fe 3 C@C composites. When the filling ratio is 50 wt%, the EMI shielding efficiency can reach 35 dB. This work suggests that magnetic/dielectric Fe/Fe 3 C@C is a good candidate in microwave absorption and EMI shielding.