Tunable Negative Permittivity in Flexible Graphene/PDMS Metacomposites
Tunable Negative Permittivity in Flexible Graphene/PDMS Metacomposites
复制标题
柔性石墨烯/PDMS超复合材料中可调谐负介电常数
DOI：
10.1021/acs.jpcc.9b06753
复制
发表时间：
2019-09-26
影响因子：
3.7
通讯作者：
Guo, Zhanhu
中科院分区：
文献类型：
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作者：
Sun, Kai;Dong, Jiannan;Guo, Zhanhu
具有可调负介电常数的柔性亚复合材料在可穿戴斗篷、可拉伸传感器和薄膜电容器等方面具有巨大的潜力。本文采用原位聚合法制备了具有可调负介电常数的柔性石墨烯/聚二甲基硅氧烷（GR/PDMS）亚复合材料。研究了不同石墨烯质量分数（0- 4wt%）的复合材料的交流电导率、介电性能和阻抗性能。随着石墨烯含量的增加，复合材料的导电机理由跳跃导电向电子导电转变，沿着发生微观结构的变化。当复合材料中石墨烯含量达到3wt%时，复合材料呈现出符合Drude模型的负介电常数。进一步的研究表明，介电常数和电抗之间存在对应关系。结果表明，负介电常数是由电感性引起的，而正介电常数是由电容性引起的。
The flexible metacomposites with tunable negative permittivity have great potential in wearable cloaks, stretchable sensors, and thin-film capacitors, etc. In this paper, the flexible graphene/polydimethylsiloxane (GR/PDMS) metacomposites with tunable negative permittivity were prepared by an in situ polymerization method. The ac conductivity behavior, dielectric property, and impedance performance of the resulting composites with different graphene mass ratios (0-4 wt %) were studied. With the increase of graphene, the conductive mechanism of the resulting composites changed from hopping conduction to electron conduction, along with the change of microstructure. When graphene content in the composites came up to 3 wt %, the negative permittivity conforming to Drude model was observed. Further investigation revealed that there is a corresponding relationship between the permittivity and the reactance. It is demonstrated that the inductive character is responsible for the negative permittivity, while the capacitive character results in the positive permittivity.