不平等的伙伴关系:聚合物供体和烯受体在产生免费费用的过程中扮演的角色不对称
Brett M Savoie1, Akshay Rao, Artem A Bakulin
1Department of Chemistry, Northwestern University , Evanston, Illinois 20208, United States.
Journal of the American Chemical Society
|January 28, 2014
概括
在有机光伏中,高效的电荷生成是通过在富勒集群中的共振合来实现的. 完整的尺寸,度和维度,而不是激励子移位,控制效率.
科学领域:
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
- 有机电子 有机电子
背景情况:
- 自然光合作用通过有序的染色体和氧化还原中心实现有效的电荷分离.
- 有机光伏 (OPV) 电池表现出不良的排序,但可以实现高量子效率.
- 传统理论难以解释无序的OPV系统中的高效率.
研究的目的:
- 研究有机光伏 (OPV) 材料中高效电荷生成的机制.
- 探索烯集群特性在电荷生成中的作用.
- 为了使实验观测与对OPV电荷动态的理论理解相协调.
主要方法:
- 在大型功能化的富勒烯集群上进行电子结构计算.
- 分析富勒烯集群大小,排序和维度.
- 计算预测与超快电光实验数据的比较.
主要成果:
- 电荷的产生是通过单子激子的共振合到高能富勒伦电子状态来促进的.
- 这种共振合绕过局部的电荷转移状态,提高效率.
- 富勒烯集群大小,度和维度被确定为控制充电生成效率的关键因素.
- 研究人员发现,刺激子脱局是独立于电荷生成效率的.
结论:
- 这项研究揭示了一种新的机制,用于在由烯电子状态驱动的OPV中高效地产生电荷.
- 富勒伦集群形态,而不是刺激子移位,对于优化OPV性能至关重要.
- 这些发现挑战了传统理论,为设计先进的有机太阳能电池提供了新的见解.
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