使用分子还原剂对合性半导体纳米晶体进行再氧化光
Jeffrey D Rinehart1, Amanda L Weaver, Daniel R Gamelin
1Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, USA.
Journal of the American Chemical Society
|September 19, 2012
概括
化学减光剂显著提高了化 (ZnSe) 纳米晶体中的光发光. 这种暂时的"redox亮化"为影响半导体性能的表面陷状态提供了洞察力.
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:
- 合性半导体纳米晶体,如化 (ZnSe),在光电子应用中至关重要.
- 它们的光发光 (PL) 特性往往受到表面缺陷或"陷状态"的限制.
- 了解和减轻这些陷状态是提高纳米晶体性能的关键.
研究的目的:
- 为了研究化学减光剂对合式ZnSe基纳米晶体光发光的作用.
- 探索氧化还原相互作用的潜力,以提高纳米晶体量子产量.
- 为了更深入地了解氧化还原活性表面陷状态.
主要方法:
- 使用的次导带潜在的化学减少剂.
- 应用外球减光剂,使合体Mn2+) 合 ZnSe 纳米晶体.
- 在减光剂添加前和后测量光发光量产量 (PLQY).
- 在不同的大气条件下观察到的效应的可逆性和稳定性.
主要成果:
- 在使用化学减光剂的基于ZnSe的纳米晶体中显示出显著的光发光增强.
- 实现了对Mn2+) 化ZnSe纳米晶的PLQY从14%大幅增加至80%.
- 在纳米晶体中观察到高达48倍的"redox亮化",但最初的量子产量较低.
- 发现这种增强在暴露于空气时是可逆的,即使在无氧条件下也是暂时的.
结论:
- 化学减光剂可以有效地增强合式ZnSe基纳米晶体的光发光.
- 观察到的"redox亮化"现象为研究表面陷状态提供了一种新方法.
- 这种方法为纳米晶体性质中氧化还原活性陷状态的作用提供了系统的见解.
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