中文版 | English
CSpace  > 微纳制造与系统集成研究中心
Synthesis of mesoporous hexagonal cobalt nanosheets with low permittivity for enhancing microwave absorption performances
Zhang, Yilin1,2; Piao, Mingxing2; Zhang, Heng2; Zhang, Feng1; Chu, Jin2; Wang, Xiao2; Shi, Haofei2; Li, Chaolong2
2019-09-15
摘要In this study, regular hexagonal cobalt (Co) nanosheets with mesoporous structure have been successfully prepared on a large scale uniformly through precursor directed synthesis route. In contrast to the traditional ball milling technique, such Co nanosheets were controllable and repeatable in lateral dimension and thickness. The radial length of the Co nanosheets was observed in the range of 3-5 mu m with the average thickness of 120 nm. Such flaky shape was proved to be beneficial to break the Snoek limit, resulting in appreciable permeability in high frequency range. In addition, the mesoporous structure is favorable of lowering the permittivity and suppressing eddy current effect. Consequently, excellent microwave absorption performances could be achieved through adequate synergy of the attenuation competence and impedance matching. The minimum reflection loss (RL) value of - 45.1 dB was realized with a thickness of 2 mm, and the effective bandwidth (RL < -10 dB) could be reached 8.5 GHz. To the best of our knowledge, this is the largest effective bandwidth compared with those of Co-based materials derived from diverse elaborate superstructures. Such unique morphology and microstructure could provide new insights to design superior microwave absorbers depending on ferromagnetic metals and a series of composites.
关键词Precursor directed synthesis Hexagonal cobalt nanosheets Mesoporous structure Superior microwave absorption
DOI10.1016/j.jmmm.2019.165272
发表期刊JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
ISSN0304-8853
卷号486页码:10
收录类别SCI
WOS记录号WOS:000471859200032
语种英语