揭示2基染料敏感太阳能电池中快速电子转移的起源
Hai Wei1,2,3, Jun-Wei Luo1,2,3, Shu-Shen Li1,2,3
1State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences , P.O. Box 912, Beijing 100083, China.
Journal of the American Chemical Society
|June 11, 2016
概括
由于更快的电子转移,二氧化 (TiO2) 在染料敏感的太阳能电池中胜过氧化 (ZnO). 在TiO2中,密度较高的状态提供了更高效的电子传输路径,解释了效率差距.
科学领域:
- 材料科学
- 太阳能发电
- 量子化学
背景情况:
- 染料敏感太阳能电池 (DSC) 中的电子转移对于效率至关重要.
- 氧化 (ZnO) 的电子流动性高于二氧化 (TiO2),但基于ZnO的DSC的效率较低.
- 基于ZnO的DSC的电子转移速度较慢是一个长期的难题.
研究的目的:
- 从染料分子到 ZnO 和 TiO2 的电子转移率进行计算研究和比较.
- 阐明电子转移动学的观察差异的根本原因.
- 提出设计原则以提高DSC的效率.
主要方法:
- 基本原则的计算.
- 马库斯的理论框架.
- 状态电子密度的分析.
主要成果:
- 基于TiO2的DSC的预测电子转移率 (1.15 × 10^9 s^-1) 比基于ZnO的DSC快15倍.
- 在导电带边缘附近的TiO2状态的较高密度有助于更快的电子转移.
- 计算结果与实验观察结果一致.
结论:
- 在DSC中TiO2的优异性能归因于其较高的状态密度,提供更高效的电子传输通道.
- 高流动性光电极半导体的表面工程可以提高DSC的效率.
- 了解电子结构是优化太阳能电池性能的关键.
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