在单层半导体中通过单片裂变敏感化产生100%以上的效率光电
Lei Ye1,2, Yujie Zhao3, Rong Xu4
1Key Laboratory of Excited-State Materials of Zhejiang Province, Department of Chemistry, Zhejiang University, Hangzhou 310058, China.
Journal of the American Chemical Society
|November 23, 2023
概括
单片裂变 (SF) 材料通过每光子产生两个激子来提高半导体效率. 这项研究揭示了有机/2D异构中最佳的电荷传递,达到126%的光电荷生成效率.
科学领域:
- 材料科学
- 太阳能发电
- 有机电子
背景情况:
- 单片裂变 (SF) 材料可以通过从一个光子产生两个激子来增强光电转换.
- 二维 (2D) 半导体提供出色的电荷传输,但光吸收有限.
- 在有机/无机界面上有效地从SF中采集三倍激子仍然是一个重大挑战.
研究的目的:
- 在有机/2D双层异构结构中研究SF敏感性.
- 阐明SF,激子解离和电荷转移之间的相互作用.
- 优化异构结构设计以增强光电充电的产生.
主要方法:
- 使用TIPS-Pc单晶制造高质量的有机/2D双层异构结构.
- 暂时的磁光谱检测超快的动态.
- 对竞争过程的分析:单体激素裂变,解离和三体激素传输.
主要成果:
- 证明了超快速的SF在100 fs以下.
- 在裂变之前在界面上确定了竞争单颗激素解离.
- 在皮秒到纳秒的时间尺度上观察到三倍激子的扩散有限的电荷转移.
- 在最佳设计的异构结构中实现了126%的显著光电充电效率.
结论:
- 单子裂变,解离和三重激子传输之间的竞争性相互作用决定了SF敏感化效率.
- 优化的有机/2D异构结构为超越2D光电子中的常规效率限制提供了有希望的途径.
- 这项工作为利用三重激子用于先进的光伏应用提供了关键的见解.
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