有效的电子道管理导电聚合物和绝缘体混合物的运输
Scott T Keene1, Wesley Michaels2, Armantas Melianas1
1Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States.
Journal of the American Chemical Society
|June 6, 2022
概括
导电聚合物混合物可以实现高电荷载体移动性,即使具有高绝缘体含量. 这是由于绝缘体中的芳香环促进了聚合物链之间的道,挑战了当前的设计范式.
科学领域:
- 材料科学
- 聚合物科学
- 凝聚物质物理学
背景情况:
- 目前用于导电聚合物 (CP) 和混合物的电子运输模型主要集中在连接链排列上.
- 在运输研究中经常忽略了CP混合物中绝缘元件的电子贡献.
研究的目的:
- 研究非导电元件的化学结构对CP混合物的电荷载体移动性的影响.
- 开发适用于不同稀释的CP混合物的多尺度运输模型.
主要方法:
- 使用原型导电聚合物混合物进行实验分析.
- 根据混合物的微观结构开发了一个单一的多尺度运输模型.
- 分析的电荷载体移动性在高达97.4%的绝缘体含量的混合物中.
主要成果:
- 具有高绝缘体含量 (高达97.4%) 的CP混合物表现出与纯CP相比的载体流动性.
- 发现绝缘元件中的芳香环可以促进隔离CP链之间的远程道 (高达3nm).
- 开发的多尺度模型准确地描述了所有测试稀释的传输特性.
结论:
- 绝缘元件的化学结构显著影响CP混合物中的电荷载体移动性.
- 由绝缘体介导的远程道化是稀释混合物的高流动性的一个关键机制.
- 重新考虑绝缘元件作为电子活性元件的作用可以提高CP性能.
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