波函数工程用于II型核心/外量子点中的超快速电荷分离和缓慢电荷重组
Haiming Zhu1, Nianhui Song, Tianquan Lian
1Department of Chemistry, Emory University, Atlanta, Georgia 30322, USA.
Journal of the American Chemical Society
|May 4, 2011
概括
像CdTe/CdSe这样的II型核心/外量子点 (QD) 呈现出超快的电荷分离和缓慢的重组. 这使得这些半导体量子点非常适合高效的太阳能转换应用.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 摄影化学的使用.
背景情况:
- 半导体量子点 (QD) 具有尺寸依赖的光学和电子特性.
- 核心/外QD通过控制电子和孔波函数定位来提供可调节的特性.
- 类型II核心/外QD,如CdTe/CdSe,空间分离电子和孔.
研究的目的:
- 为了研究II型CdTe/CdSe-化 (AQ) 复合体中的电荷转移动态.
- 评估II型QDs在太阳能转换方面的潜力.
主要方法:
- 超快速的短暂吸收光谱学.
- 在CdTe/CdSe核心/外量子点的制造.
- 作为一个电子受体,吸炭 (AQ) 的吸附.
主要成果:
- 从CdTe核心到CdSe外观察到超快的QD内电子转移 (~770 fs).
- 证明了从外向吸附的AQ (2.7ps半衰期) 的电子转移.
- 与CdSe-AQ复合物相比,显示显著延迟的电荷重组 (92 ns半衰期).
结论:
- 第二种类型的CdTe/CdSe QD可促进超快速的电荷分离和缓慢的重组.
- 这种特性提高了光采集应用的效率.
- 第二种类型的QD是用于先进太阳能转换的有希望的材料.
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