碳包覆NiO@Ni纳米复合物微波吸收性能研究

Microwave absorption of carbon encapsulated Ni@NiO nanocomposites

由于微波吸收材料在军事和民间的广泛应用,近年来微波吸收研究受到人们广泛地关注。本文成功合成了具有核壳结构的NiO@Ni@C纳米复合物。利用X射线衍射仪、扫描电镜、透射电镜和矢量网络分析仪研究NiO@Ni@C纳米复合物的晶体结构、形貌以及微波吸收性能。结果表明:碳均匀的包覆在磁性纳米颗粒NiO@Ni的表面。在微波频率在1~18 GHz范围内研究了NiO@Ni@C纳米复合物的微波吸收性能。NiO@Ni@C 2/1具有优异的微波吸收性能,微波吸收性能明显好于NiO@Ni@C 1/2和NiO@Ni@C 1/1。在微波频率为6.1 GHz,厚度为3.76 mm时,NiO@Ni@C 2/1的最小RL值可以达到-52.0 d B。在厚度为2.5 mm时,RL值低于-10 d B的吸收频宽为3.2 GHz(微波频率从8.3到11.5 GHz)。

Due to the wide applications of microwave absorbing materials,microwave absorption research has received wide attention in recent years. The core-shell structured Ni@NiO@C nanocomposites were synthesized successfully. The crystal structure,morphology and microwave absorption performance of the Ni@ NiO@ C nanocomposites were studied by XRD,SEM,TEM and vector network analyzers. The results showed that the Ni@ NiO magnetic nanoparticles were coated by carbon. The microwave absorption performance of the Ni@ NiO@ C nanocomposites was studied in the frequency of 1 ～ 18 GHz. The Ni@ NiO@ C 2/1 nanocomposite has more excellent performance,compared with Ni@ NiO@ C 1/2 and Ni@ NiO@ C 1/1 nanocomposites. For the Ni@NiO@ C 2/1 nanocomposite,the minimum reflection loss（ RL） of-52. 0 d B was achieved at 6. 1 GHz for the thickness of 3. 76 mm and,as the thickness is decreased down to 2. 5 mm,the microwave absorption bandwidth reaches 3. 2 GHz（ 8. 3 ～ 11. 5 GHz） under the RL lower than-10 d B.