Wen Junwu, Li Xuexiang, Chen Geng, Wang Zhenni, Zhou Xuejiao, Wu Hongjing
School of Advanced Materials and Nanotechnology, Xidian University, Xi'an 710071, China.
MOE Key Laboratory of Material Physics and Chemistry under Extraordinary, Northwestern Polytechnical University, Xi'an 710072, China.
J Colloid Interface Sci. 2021 Jul 15;594:424-434. doi: 10.1016/j.jcis.2021.03.056. Epub 2021 Mar 17.
Core-shell structural cobalt- and nickel-based metal oxides with different compositions have rarely been reported as electromagnetic wave absorption materials. Herein, core-shell structural CoO@NiCoO composites have been successfully fabricated via simple etching and deposition reaction of Co-based metal-organic framework with subsequent calcination in air. According to morphological evolution, it is verified that the cavity volume between CoO core and NiCoO shell could be modulated effectively by simply controlling proton etching and deposition reaction. The electromagnetic wave absorption properties of the CoO@NiCoO composites were investigate. It was demonstrated that multiple interfacial polarization of heterogeneous interfaces involving cavities, such as CoO/Void, Void/NiCoO and CoO/NiCoO have made great contribution to the excellent electromagnetic wave absorption performance. CoO@NiCoO with optimized microstructure exhibited RL value as strong as -34.42 dB with a broad effective absorption bandwidth up to 4.88 GHz at a layer thickness of 2.6 mm. It is believed that core-shell structural cobalt- and nickel-based metal oxides will become an excellent candidate for high-performance electromagnetic wave absorber.
具有不同组成的核壳结构钴基和镍基金属氧化物作为电磁波吸收材料鲜有报道。在此，通过钴基金属有机框架的简单蚀刻和沉积反应，随后在空气中煅烧，成功制备了核壳结构的CoO@NiCoO复合材料。根据形态演变，证实了通过简单控制质子蚀刻和沉积反应，可以有效地调节CoO核与NiCoO壳之间的空腔体积。研究了CoO@NiCoO复合材料的电磁波吸收性能。结果表明，涉及空腔的异质界面的多重界面极化，如CoO/空隙、空隙/NiCoO和CoO/NiCoO，对优异的电磁波吸收性能起到了很大的作用。具有优化微观结构的CoO@NiCoO在2.6mm的层厚度下表现出高达-34.42dB的反射损耗值，有效吸收带宽高达4.88GHz。相信核壳结构的钴基和镍基金属氧化物将成为高性能电磁波吸收体的优秀候选材料。
