一种新型碳纳米纤维的电磁性能研究

细菌纤维素在一定温度下碳化, 得到一种三维网状结构的纳米碳化纤维(CBC), 利用X射线衍射仪、拉曼光谱仪和透射电子显微镜对这种新型碳纤维进行了分析表征。将 CBC与石蜡按一定比例复合, 采用矢量网络分析仪在0.1~18 GHz 范围处测试了其电磁参数, 发现此复合材料具有较大的介电常数实部和虚部, 特别是在频率较低时, 具有很大的介电损耗。将少量 CBC 与Fe₃O₄ 纳米颗粒复合, 可极大地改善磁性颗粒的微波吸收性能, 当样品厚度为1.2 mm时, 反射损耗(RL)最小值从-2 dB 降至-21 dB。

Electromagnetic Properties of Novel Carbon Nanofibers

Carbonized bacterial cellulose (CBC) with a three dimensional net-linked framework were synthesized from carbonized bacterial cellulose and investigated by X-ray diffraction, Raman spectrum and Transmission electron microscopy. The complex permittivity and permeability of CBC/paraffin wax composite with certain ratio of the composite were measured by vector network analysis in the frequency range of 0.1-18 GHz. It is found that the composite has high permittivity and dielectric loss, especially at the low frequency. The electromagnetic characteristics of the CBC/Fe₃O₄ complex absorbers synthesized by mixing a small quantity of CBC with Fe₃O₄ were also studied, aiming at improving the microwave absorbing properties of Fe₃O₄/Wax composite. When the sample’s thickness was 1.2 mm, the reflection loss reached a minimal value of -21 dB for CBC - Fe₃O₄/Wax and of -2 dB for Fe₃O₄/Wax as well.