在水性/非水性电解质混合物中的染料敏感的SnO2/TiO2电极中的电子转移动力学
Langqiu Xiao1, Jacob A Spies2,3, Colton J Sheehan1
1Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States.
Journal of the American Chemical Society
|June 20, 2024
概括
优化染料敏感的太阳能电池需要调整电解质. 混合溶剂通过控制半导体平带电位来提高SnO2/TiO2核心/外光电极的电子注入效率.
科学领域:
- 材料科学
- 摄影化学
- 光谱学
背景情况:
- 染料敏感型太阳能电池 (DSSC) 是一个有前途的可再生能源技术.
- 有效的光诱导电子转移对于DSSC的性能至关重要.
- 了解溶剂对电子转移动态的影响是优化的关键.
研究的目的:
- 研究溶剂组成对染料敏感光电极的光诱导电子转移动态的影响.
- 在SnO2/TiO2核心/外结构中阐明电子注入的机制.
- 要将依赖于溶剂的电子特性与注入效率相关联.
主要方法:
- 纳米秒暂时吸收光谱 (TAS) 用于测量电子转移动态.
- 超快的光学太赫兹探针光谱 (OPTP) 来探测电荷载体的行为.
- 用染料敏感的SnO2/TiO2核心/外和TiO2电极的制造和表征.
主要成果:
- 混合溶剂电解质显著提高了SnO2/TiO2核心/外电极的电子注入效率.
- 乙二的度增加降低了TiO2电极的注入效率,与半导体平带电位的负变化相关.
- 核/外电极的两步注入过程被证实,在TiO2中超快速捕获,然后转移到SnO2.
- 在SnO2核心中观察到负光导,这归因于电场诱导的核心/外接口的捕获.
结论:
- 电解质成分极大地影响着染料敏感的光电极中的电子注入和电荷分离.
- 混合溶剂电解质为优化SnO2/TiO2核心/外光电极性能提供了有效的策略.
- 观测到的负光导电性为界面电荷动态和潜在损耗机制提供了洞察力.
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