硫化物氧化还原电解质对量子点的充电降低了量子点敏感太阳能电池中电子注入的效率
Haiming Zhu1, Nianhui Song, Tianquan Lian
1Department of Chemistry, Emory University, Atlanta, Georgia 30322, USA.
Journal of the American Chemical Society
|July 20, 2013
概括
太阳能电池中的量子点 (QD) 可以被电解质充电,缩短它们的寿命并降低效率. 这种充电效应影响了QD光伏和光催化装置的设计.
科学领域:
- 材料科学 材料科学 材料科学
- 太阳能光伏发电是如何实现的
- 纳米技术 纳米技术
背景情况:
- 量子点敏感太阳能电池 (QDSSCs) 使用氧化还原电解质进行洞清理以再生QDs.
- 与分子敏感剂不同,QDs在其带隙内具有氧化还原活性陷状态,易受电解质诱导的充电.
- 电解质诱导的QD充电对QDSSC性能的影响在很大程度上仍未被探索.
研究的目的:
- 研究电解质诱导充电对核心/多量子点 (QD) 的光物理性质的影响.
- 阐明电解质充电影响QDSSC激子动态和电子注入效率的机制.
主要方法:
- 利用稳定状态和时间分辨率的吸收和发射光谱学.
- 在硫化物电解质的存在下,研究了CdSe/CdS3MLZnCdS2MLZnS2ML核心/多质QD.
主要成果:
- 证明CdSe/CdS核心/多质QD在硫化物电解质中因表面状态减少而充电.
- 在充电的QD中观察到刺激子寿命的缩短,归因于增强的Auger重组.
- 表明充电诱导的Auger重组与电子转移到TiO2竞争,从而降低了电子注入效率.
结论:
- 电解质诱导的QD充电显著影响其激电动力学和电荷转移过程.
- 由充电触发的快速Auger重组可以限制QDSSC的性能.
- 这些发现对基于合纳米晶的光伏和光催化应用的设计和优化具有广泛的影响.
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