当三重体状态不重要时:洞察其对VOC的影响
Mohammad Saeed Shadabroo1, Nurlan Tokmoldin2, Atul Shukla1
1Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam-Golm, Germany.
概括
有机太阳能电池通过最大限度地减少重组损失来实现高效率. 这项研究表明,长三倍寿命使三倍激子解离成为可能,减少有机太阳能电池中的电压损失.
科学领域:
- 有机电子学有机电子学
- 太阳能光伏发电是如何实现的
- 材料科学是一种材料科学.
背景情况:
- 有机太阳能电池 (OSC) 的效率受到单元和三元电荷转移 (CT) 状态和三元激子的重组损失的限制,影响开放电路电压 (Voc).
- 尽量减少这些损失对于提高OSC绩效至关重要.
研究的目的:
- 研究三重激子在有机太阳能电池中的重组损失中的作用.
- 阐明三重刺激子解离可以减少电压损失的机制.
- 展示一项战略,以最大限度地减少高效率的OSC中的三重相关能源损失.
主要方法:
- 使用PM6:o-IDTBR有机太阳能电池系统作为模型.
- 分析了三倍激子寿命和电荷转移状态衰变之间的相互作用.
- 量化三倍激素密度和三倍介导的重组.
主要成果:
- 在PM6:o-IDTBR中实现了160mV的低非辐射电压损失 (ΔVoc),尽管有显著的三重激子群 (6 × 10^15cm^-3).
- 证明一个长的三倍生命周期 (10微秒) 促进三倍激子解离到CT状态.
- 通过三倍体介导的再组合限制在约10%左右.
结论:
- 当三重激子寿命超过CT衰变寿命时,三重激子向CT状态的解离是一个可行的过程.
- 这一过程有效地减少了源自T1状态的能量损失道.
- 这些发现为最大限度地减少电压损失和提高有机太阳能电池效率提供了途径.
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