用匹配的辅助剂修改聚二甲基四烯结构以获得高且主要非离子导电性
Hui Li1, Mallory E DeCoster2, Robert M Ireland1
1Department of Materials Science and Engineering, Johns Hopkins University , 3400 North Charles Street, Baltimore, Maryland 21218, United States.
Journal of the American Chemical Society
|July 25, 2017
概括
基于聚二甲四烯的新型聚合物具有高导电性和稳定性. 修改增强了氧化性,从而在电子应用的薄膜中记录了非离子导电性.
科学领域:
- 材料科学
- 有机电子
- 聚合物化学
背景情况:
- 聚二甲基四二烯 (PQT12) 是有机电子产品的基聚物.
- 提高p型聚合物的氧化性对于提高性能至关重要.
- 现有的导电聚合物通常存在不稳定性或依赖外部离子贡献.
研究的目的:
- 合成和表征具有增强导电性和稳定的新型聚合物.
- 研究特定化学修饰对聚合物特性的影响.
- 评估这些新材料在电子应用中的潜力.
主要方法:
- 合成四种经过修饰的聚二甲基四二烯 (PQT12) 聚合物.
- 将硫原子和/或3,4-乙二氧化基纳入PQT12结构.
- 用NOBF4和四基二甲 (F4TCNQ) 对聚合物进行注和导电性测量.
- 稳定性,电荷转移,π-π堆叠,分子间合,西贝克系数,功率因子和导热性.
主要成果:
- PQTS12 (硫基改性) 的导电率为350 S cm-1,这是多聚合物溶液中报告的最高非离子导电率.
- PDTDE12 (乙烯二氧化物修饰) 的导电率为140 S cm-1.
- 导电性在空气中稳定,在稳定性和缺乏外部离子贡献方面表现优于PEDOT:PSS.
- 有效的电荷转移,更紧密的π-π堆叠和强大的分子间合被确定为高导电性的关键因素.
- 观察到1-5cm2V-1s-1的移动性增加,得到了场效应晶体管研究的支持.
- 导热聚合物 (0.2-0.5 W m-1 K-1) 的热导率是典型的.
结论:
- 合成的p型聚合物具有出色的导电性和稳定性.
- 化学修饰显著提高了聚合物的氧化性和电子性质.
- 这些材料对先进的有机电子设备具有前景,并有可能通过提高移动性来进一步改进.
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