具有超长载体寿命的红外活性异构纳米晶体
Doh C Lee1, István Robel, Jeffrey M Pietryga
1Center for Advanced Solar Photophysics, MS-J567, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
Journal of the American Chemical Society
|July 3, 2010
概括
我们合成了新的化/化/硫化 (PbSe/CdSe/CdS) 纳米晶体. 这些红外发射纳米结构显示出延长载体寿命和高效率,对先进的应用有希望.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 量子点就是量子点.
背景情况:
- 半导体纳米晶体提供可调节的光学特性.
- 控制载体动态对于光电子应用至关重要.
研究的目的:
- 为了合成和描述新的复合物PbSe/CdSe/CdS纳米晶体.
- 为了研究纳米晶体几何和载体寿命之间的关系.
- 探索红外光电子的潜在应用.
主要方法:
- 核心/外/外和四足体PbSe/CdSe/CdS纳米晶体的合成.
- 结构和光学属性的表征.
- 时间分辨率光发光谱法测量载体衰变时间.
主要成果:
- 实现了两个不同的PbSe/CdSe/CdS纳米晶体几何体的合成.
- 观察到极长的载体衰变时间 (高达20微秒).
- 证明了高的红外辐射效率.
- 相关的延长寿命,由于电子移位,减少了电子孔重叠.
结论:
- 有控制几何形状的复合PbSe/CdSe/CdS纳米晶体表现出优越的载体寿命和排放效率.
- 这些纳米结构是红外激光,光催化和光伏的有希望的候选者.
- 这些发现为设计用于光电子设备的先进纳米材料开辟了新的途径.
相关概念视频
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