在有机/2D半导体混合激发性异构中进行长距离热电荷转移激发分离
Zukun Wang1,2, Cheng Sun1,2, Xuehui Xu3
1Key Laboratory of Excited-State Materials of Zhejiang Province, Department of Chemistry, Zhejiang University, Hangzhou 310027, China.
Journal of the American Chemical Society
|May 9, 2023
概括
这项研究调查了有机/2D半导体异构结构,发现了快速,无障碍的电子孔对在1ps内分离. 地方有机晶体, 而不是二维移位, 驱动了光电子的关键电荷分离.
科学领域:
- 材料科学
- 固态物理
- 物理化学
背景情况:
- 电子孔对在供体接口上的分离对于光电子学至关重要.
- 在有机/2D半导体异构结构中选较差的库伦相互作用使电荷分离复杂化.
- 了解这些新兴系统的电荷动态至关重要.
研究的目的:
- 在有机/2D异构结构中直接追踪电子孔对分离.
- 阐明这些系统中电荷分离的机制.
- 确定影响电荷转移和分离效率的因素.
主要方法:
- 暂时吸收光谱来监测电荷动态.
- 分离电荷的电吸收 (斯塔克效应) 信号的跟踪.
- 使用模型系统:氧化瓦纳/单层MoS2.
主要成果:
- 观察到小于100 fs的界面电子转移,随后是快速的电荷分离.
- 证明无障碍的长距离电子孔对与自由载体的分离在1秒内.
- 确定局部有机晶体是电荷移位的关键,而二维半导体移位的影响最小.
结论:
- 热电荷转移激子解离促进了快速的电荷分离.
- 有机层中的局部秩序对于有效的电荷移位和分离至关重要.
- 这些发现协调了电荷转移激子的发射和解离,指导了未来的光电子器件开发.
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