Chen Nankun, Xiao Yiyao, Wang Chao, He Jiahao, Song Ningning
College of Mathematics and Physics, Beijing University of Chemical Technology, Beijing 100029, China.
ACS Appl Mater Interfaces. 2023 Oct 18;15(41):48529-48542. doi: 10.1021/acsami.3c10316. Epub 2023 Oct 5.
Ternary hierarchical FeO@C@MoS composites and binary hierarchical FeO@C composites were successfully fabricated by a modified mixed solvothermal method, a self-oxidation polymerization method, and a hydrothermal process. Their magnetic properties and microwave absorption performance were investigated. Dual resonance behavior was observed in the FeO@C@MoS composites. One of the resonances was attributed to natural resonance with a resonance frequency of 2.58 GHz, which was much higher than that for FeO bulk (1.5 GHz). The other originated from the superparamagnetic/ferromagnetic relaxation with a resonance frequency of 12.45 GHz. The minimum reflection loss (RL) reached -64.30 dB with a matched thickness of 2.24 mm at 11.64 GHz, and the maximum effective absorption bandwidth (EAB) covered 6.39 GHz with a matched thickness of 1.89 mm. In addition, the maximum Radar cross section (RCS) reduction value reached 31.90 dB m at a scattering angle of 0°. Electron holography analysis confirmed a dense magnetic absorption network in the FeO@C@MoS composites. The boost in microwave absorption performance was caused by the synergistic effects of magnetic and dielectric properties owing to the ternary hierarchical structure, shape magnetic anisotropy, and incorporation of 1T/2H MoS. Besides, the binary hierarchical FeO@C composites also exhibited good absorbing performance caused by natural resonance, with an RL of -52.90 dB at 5.80 mm, an EAB of 5.98 GHz at 3.38 mm, and a relatively high RCS reduction value of 13.04 dB m at θ = 20°. This work paves the way for designing multicomponent hierarchical absorbers with broadband and intensive microwave absorption.
通过改进的混合溶剂热法、自氧化聚合法和水热法成功制备了三元分级FeO@C@MoS复合材料和二元分级FeO@C复合材料。研究了它们的磁性能和微波吸收性能。在FeO@C@MoS复合材料中观察到双共振行为。其中一个共振归因于自然共振，共振频率为2.58 GHz，远高于块状FeO的共振频率（1.5 GHz）。另一个共振源于超顺磁/铁磁弛豫，共振频率为12.45 GHz。在11.64 GHz时，最小反射损耗（RL）达到-64.30 dB，匹配厚度为2.24 mm，最大有效吸收带宽（EAB）覆盖6.39 GHz，匹配厚度为1.89 mm。此外，在0°散射角下，最大雷达散射截面（RCS）降低值达到31.90 dB m。电子全息分析证实了FeO@C@MoS复合材料中存在致密的磁吸收网络。微波吸收性能的提升是由于三元分级结构、形状磁各向异性以及1T/2H MoS的掺入导致的磁性能和介电性能的协同效应。此外，二元分级FeO@C复合材料也由于自然共振而表现出良好的吸收性能，在5.80 mm处RL为-52.90 dB，在3.38 mm处EAB为5.98 GHz，在θ = 20°时RCS降低值相对较高，为13.04 dB m。这项工作为设计具有宽带和强微波吸收的多组分分级吸收体铺平了道路。
