通过选择 counterion 来控制发光二极管中的化聚合物性能
Renqiang Yang1, Hongbin Wu, Yong Cao
1Mitsubishi Chemical Center for Advanced Materials, Department of Materials, Institute for Polymers and Organic Solids, University of California, Santa Barbara, California 93106, USA.
Journal of the American Chemical Society
|November 9, 2006
概括
修改合聚电解质中的对电离子显著影响其作为有机发光二极管 (OLED) 中电子传输层的性能. 诸如四基 (imidazolyl) 酸盐等特定的对应物增强了OLED的效率,使得使用稳定的阴极金属成为可能.
科学领域:
- 材料科学 材料科学 材料科学
- 有机电子 有机电子
- 聚合物化学 聚合物化学
背景情况:
- 结合的多电解质作为有机发光二极管 (OLED) 中的电子传输层 (ETL) 是至关重要的.
- ETL的性能对材料属性,包括 counterions.敏感.
- 模块化电路提供了一个直接的路线来调整ETL功能.
研究的目的:
- 为了研究对电离子交换对OLED中作为ETL使用的电离子结合聚电解质的性能的影响.
- 为了确定不同 counterions 和设备效率之间的结构属性关系.
主要方法:
- 合成[9,9-bis6'-N,N,N-trimethylammonium) -hexyl) ]化物 (PF-Br) 与各种对应物:三甲硫酸盐 (PF-CF3SO3),四甲 (PF-BIm4) 和四甲 (3,5-trifluoromethylphenyl) (PF-BArF4).
- 通过降水和冲洗进行对流交换.
- 使用MEH-PPV作为发射层和修改过的多电解质作为ETL的OLED设备的制造和表征.
主要成果:
- 设备的性能随着对手的选择而有显著差异,按照以下顺序:PF-BIm4 > PF-CF3SO3 > PF-Br > PF-BArF4.
- 使用PF-BIm4作为ETL的OLED实现了与阴极相比的光效率.
- 选择的 counterion 影响电子注射效率,并允许使用更高的工作功能,更稳定的阴极材料.
结论:
- 对比工程是一种有效的策略,可以优化OLED中合多电解质ETL的性能.
- 甲基 (imidazolyl) 酸对子体表现出卓越的性能,使得有效的电子注射成为可能.
- 这种方法可以在OLED制造中使用坚固和稳定的正极材料,而不会影响设备的效率.
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