Co@CNT复合电磁波吸收剂的制备及其吸波性能

以石墨相氮化碳(g-C₃N₄)和六水合硝酸钴为原料制备Co@CNT复合电磁波吸收剂，调节Co元素含量以提高其电磁波吸收性能。采用X射线衍射(XRD)、X射线光电子能谱(XPS)、拉曼光谱、扫描电镜(SEM)、能谱分析(EDS)和透射电镜(TEM)等手段表征其微结构和物相组成，使用矢量网络分析仪测量复合物电磁参数并进行Matlab模拟得到反射损耗图。结果表明，Co@CNT-1与石蜡质量比为1：3的材料，其吸波性能最优，厚度为4.1 mm时对电磁波的吸收最强，最小反射损耗(RL_min)为-45.5 dB;厚度仅为1.5 mm的材料，有效吸收带宽(RL<-10 dB)最大为4.42 GHz。

Preparation and Electromagnetic Wave Absorbing Properties of Composites of Cobalt Coated Graphitic Carbon Nitride Co@CNTs

The composite of cobalt coated graphitic carbon nitride (g-C₃N₄) (Co@CNT) for electromagnetic wave (EMW) absorption was prepared via two-step process of co-deposition and calcination with graphitic carbon nitride (g-C₃N₄) and cobalt nitrate hexahydrate as raw materials. The optimal outstanding capacity of EMW absorption of the prepared Co@CNT can be realized through adjusting the Co content of Co@CNTs. The microstructure and phase composition of Co@CNT were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, scanning electron microscopy (SEM) with Energy Disperse Spectroscopy (EDS) and transmission electron microscopy (TEM). The electromagnetic parameters and reflection loss (RL) of the composite were measured by vector network analyzer and then the reflection loss diagram is acquired by MATLAB simulation. The results show that EMW absorption performance of Co@CNT-1 is the best when it is mixed with paraffin (mass ratio 1:3). The maximum effective absorption bandwidth (RL<-10 dB) is 4.42 GHz, while the minimum reflection loss (RL_min) is up to -45.5 dB, which were measured with a hollow ring of 7 mm in outer diameter and 1.5 mm in thickness.