摘要
目的研究不同的纳米结构对Fe3O4纳米材料微波吸收性能的影响。方法采用水热法和高温碳热还原法,获得了纳米纺锤体、纳米管和开口空心球结构的三种磁性Fe3O4纳米材料,采用XRD、SEM和矢量网络分析仪研究了其物相、形貌和电磁特性。结果在这三种结构纳米Fe3O4材料中,空心球结构具有最小的介电常数和最高的波阻抗匹配系数,其磁损耗表现出双共振特性,且在7.5~14.3 GHz范围内,Fe3O4开口空心球的衰减系数明显高于另外两种结构的Fe3O4纳米材料,有利于拓宽材料的微波吸收带宽。在1.8~3.0 mm厚度范围内,Fe3O4开口空心球的反射损耗带宽均大于其他两种结构,在2.2 mm厚度下达到了5.0 GHz的有效吸收带宽(90%吸收),覆盖的频率范围为7.3~12.3 GHz。结论Fe3O4开口空心球由于特殊的结构而产生的双磁共振特性,增强了材料的微波衰减能力和阻抗匹配特性,其微波吸收能力明显优于纳米纺锤体和纳米管。经过超结构设计,可以实现宽带微波吸收。
The work aims to explore the effects of different nano-structures on the microwave absorption properties of Fe3O4 nanomaterials.The magnetic Fe3O4 nanomaterials with the morphologies of nanospindles,nanotubes and opened-hollow spheres were obtained by hydrothermal method and carbothermal reduction method.The phase,morphology and electromagnetic properties of the materials were tested by XRD,SEM and vector network analyzer.Among the Fe3O4 composites with three morphologies,opened-hollow spheres exhibited the smallest dielectric constant and the highest impedance matching coefficient,and its magnetic loss exhibited two resonance peaks,and the attenuation coefficient of the Fe3O4 opened-hollow spheres was significantly higher than the other two Fe3O4 nanomaterials in the frequency range of 7.5~14.3 GHz,which were beneficial for widening the microwave absorption bandwidth.The reflection loss bandwidth of the Fe3O4 opened-hollow spheres was larger than the other two structures in the thickness range of 1.8~3.0 mm,achieving a qualified absorption bandwidth of 5.0 GHz(90%absorption)covering from 7.3 to 12.3 GHz at the thickness of 2.2 mm.The double magnetic resonances of the Fe3O4 opened-hollow spheres enhance the microwave attenuation and impedance matching characteristics of the material.The microwave absorption capacity of the opened-hollow spheres is significantly better than nanospindles and nanotubes.Through the design of superstructure,the microwave absorption by bandwidth can be realized.
作者
王殿杰
侯志灵
WANG Dian-jie;HOU Zhi-ling(School of Sciences,Beijing University of Chemical Technology,Beijing 100029,China)
出处
《表面技术》
EI
CAS
CSCD
北大核心
2020年第2期61-67,共7页
Surface Technology
基金
国家自然科学基金（51132002）
北京化工大学学科建设基金（XK1702)~~
关键词
四氧化三铁
阻抗匹配
介电特性
微波吸收
宽带吸收
Fe3O4
impedance matching
dielectric property
microwave absorption
broadband absorption
