在核心外结构中优化外层的介电常数,以提高聚合物纳米复合材料的能量密度
Quan-Ping Zhang1, Fang-Yan Du1, Xiu Liu1
1State Key Laboratory of Environment-friendly Energy Materials, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010, China. zhangqp@swust.edu.cn.
Physical chemistry chemical physics : PCCP
|June 28, 2023
概括
涂在酸纳米颗粒上的聚合物可改善聚合物纳米复合材料的能量储存. 这种方法提高了介电性质和断裂强度,这对于小型电容器至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物科学 聚合物科学
- 纳米技术纳米技术
背景情况:
- 聚合物介电材料对于储能电容器至关重要,但增强介电性质往往会因为局部电场度而损害故障强度.
- 核心外结构用于改善聚合物纳米复合材料中的纳米粒子分散和界面兼容性.
研究的目的:
- 开发一种简单的方法来提高聚合物纳米复合材料的储能密度.
- 研究聚合物外特性对酸/聚合物纳米复合物的介电性能的影响.
主要方法:
- 通过涂覆不同含量的聚合物 (PF0,PF30,PF60) 覆盖酸 (BT) 来合成核心外纳米粒子.
- 通过将BT@PF核心外纳米颗粒与聚乙烯化物-co-hexafluoropropylene (P(VDF-HFP)) 混合制造的聚合物纳米复合材料.
- 描述了由此产生的纳米复合材料的结构,介电和储能特性.
主要成果:
- 纳米复合材料表现出均的纳米粒子分散和出色的界面兼容性.
- 介电常数随着聚合物外的含量增加而增加,为BT@PF60.12达到9.12.
- BT@PF30/P(VDF-HFP) 纳米复合材料实现了最高的分解强度 (455 kV mm−1) 和最大的放电能量密度 (11.56 J cm−3 在 485 kV mm−1).
结论:
- 调整聚合物外的介电性质有效地将纳米粒子,外和矩阵之间的介电常数结合起来.
- 这种方法减轻了局部电场度,从而提高了聚合物纳米复合材料的分解强度和电能储存.
- 开发的方法为设计用于先进电子和电气系统的高性能介电材料提供了一个有前途的途径.
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