有机半导体中的混乱和光生成效率
Artem V Toropin1, Vladimir R Nikitenko1, Nikolai A Korolev1
1National Research Nuclear University "MEPhI" (Moscow Engineering Physics Institute), Moscow 115409, Russia.
The journal of physical chemistry letters
|August 28, 2023
概括
在有机半导体中异常强烈的热双胞胎扩散增加了光生成的量子产量. 这一发现与实验结果一致,并挑战了在低温下标准的Onsager模型预测.
科学领域:
- 固态物理 固态物理
- 有机电子学有机电子学
- 摄影化学的使用.
背景情况:
- 双质对的分离对于有机半导体的电荷产生至关重要.
- 恩萨格模型描述了电荷对重组,但可能无法完全捕捉初始的"热"激子动态.
- 已知有机半导体中的能量障碍会影响电荷载体的行为.
研究的目的:
- 在有机半导体中提供双对分离概率的分析描述.
- 为了研究初始"热"双胞胎扩散对光生成量子产量的影响.
- 将理论预测与实验和模拟数据进行比较.
主要方法:
- 双胞胎对扩散的分析建模.
- 将能量扰乱效应纳入扩散模型.
- 与现有的蒙特卡洛模拟和实验光生成数据进行比较.
主要成果:
- 描述了由于能量障碍导致的"热"双胞胎异常强烈的初始扩散.
- 在低温下观察到光生成量子产量的显著增加.
- 与Onsager模型预测相比,发现量子产量的温度依赖性减弱.
结论:
- 最初的"热"双扩散显著提高了有机半导体中的光生成量子产量.
- 能量障碍在修改电荷分离动态方面发挥着至关重要的作用.
- 这些发现与实验观测和蒙特卡洛模拟相一致,表明"热"物种的标准Onsager模型的局限性.
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