合物矿中的非线性载体相互作用和缺陷的作用
Ajay Ram Srimath Kandada1, Stefanie Neutzner1,2, Valerio D'Innocenzo1,2
1Center for Nano Science and Technology @Polimi, Istituto Italiano di Tecnologia , via Giovanni Pascoli 70/3, 20133 Milano, Italy.
Journal of the American Chemical Society
|September 27, 2016
概括
通过激发相关光发光谱 (ECPL) 检测化矿的缺陷,发现浅层缺陷可以提高光发光量子产量. 这项工作为稳定,可靠的光电子设备提供了材料工程指南.
科学领域:
- 材料科学
- 固态物理
- 光电子产品
背景情况:
- 化 Perowskites 提供溶液可加工性,但存在意外缺陷,影响稳定性和可靠性.
- 了解缺陷的性质及其在设备操作中的作用对于矿光电子产品的市场规模应用至关重要.
研究的目的:
- 通过ECPL光谱来研究基矿的载体重组动态和缺陷能量.
- 量化描述载体捕获动态,并将制造条件与非辐射损失通道相关联.
主要方法:
- 激发相关光发光谱 (ECPL)
- 描述载体捕获动态的Shockley-Read-Hall形式主义的概括.
- 缺陷能量和多体相互作用的分析.
主要成果:
- 在多晶化膜中发现了深层和浅层的载体陷.
- 在半导体中发现的浅缺陷 (传导带以下20 meV) 增强了光发光的量子产量.
- 在高激发密度下,由于相对应的光载体模式,观察到非辐射的奥格尔重组抑制.
- 展示了状纳米晶体作为几乎无缺陷的系统,主要来自Auger类相互作用的非辐射火.
结论:
- ECPL光谱是一种敏感的工具,用于识别矿的缺陷能量和重组动态.
- 材料工程策略可以通过将制造条件与已识别的非辐射损失道相关联来指导.
- 浅缺陷可以有益于矿,而合纳米晶体则为先进的光电子系统提供了缺陷最小化的途径.
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