无化 Perowskite纳米晶体的合成和光学特性
Tom C Jellicoe1, Johannes M Richter1, Hugh F J Glass1
1Cavendish Laboratory, University of Cambridge , J.J. Thomson Avenue, Cambridge, CB3 0HE, United Kingdom.
Journal of the American Chemical Society
|February 23, 2016
概括
研究人员开发出基于锡的矿纳米晶体, 提供无毒的可调光发射. 这些新材料通过量子封闭和离子控制表现出高效的发光,为更安全的光电子铺平了道路.
科学领域:
- 材料科学
- 纳米技术
- 固态物理
背景情况:
- 由于其可加工性和光学特性,金属化是有前途的光电子材料.
- 在矿纳米晶体中的量子封闭增强了光谱可调性和发光.
- 基于的矿阻碍了商业化;正在寻找无替代品.
研究的目的:
- 使用锡合成和表征无晶体.
- 通过量子封闭和基矿中的离子组成来证明光谱可调性.
- 研究这些新型纳米晶体的发光机制和时间尺度.
主要方法:
- 合成CsSnX3 (X=Cl,Cl0.5Br0.5,Br,Br0.5I0.5,I) 的矿纳米晶体.
- 光学属性的表征,包括光谱可调性.
- 时间分辨率发光光谱分析衰变过程.
主要成果:
- 成功合成可调的CsSnX3矿纳米晶体.
- 通过量子封闭和化物组成的控制证明了光谱调性.
- 在皮秒到纳秒的时间尺度上确定了两个不同的辐射衰变过程 (带对带和缺陷相关).
结论:
- 基于锡的矿纳米晶体为光电子应用提供了可行的无替代品.
- 量子封闭和离子工程是调整它们光学属性的有效策略.
- 了解发光路径对于优化基于Sn的矿纳米晶体的性能至关重要.
相关概念视频
Ionic Crystal Structures
Ionic crystals consist of two or more different kinds of ions that usually have different sizes. The packing of these ions into a crystal structure is more complex than the packing of metal atoms that are the same size.
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
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Imperfections in Crystal Structure: Non-Stoichiometric Defects
Non-stoichiometric defects refer to a type of defect in the crystal structure of a compound where the ratio of its constituent elements deviates from the ideal stoichiometric ratio. There are two main types of non-stoichiometric defects: metal excess defects and metal deficiency defects.Metal excess defects occur when there is a slight surplus of metal ions than what is required by the stoichiometric ratio of the compound. For example, heating a sodium chloride crystal in sodium vapor results...


