通过二维II-VI纳米晶体的可逆表面交换进行大的激发能量转移
Yang Zhou1, Fudong Wang1, William E Buhro1
1Department of Chemistry, Washington University , Saint Louis, Missouri 63130-4899, United States.
Journal of the American Chemical Society
|November 17, 2015
概括
化 (CdSe) 和硫化 (CdS) 量子纳米结构的表面被动化可以在氨基联体和金属碳酸盐之间进行可逆切换. 这种连接物交换会影响量子点的光学特性和应变状态.
科学领域:
- 材料科学
- 纳米技术
- 量子点研究
背景情况:
- 量子点 (QD) 是具有可调节光学和电子特性的半导体纳米晶体.
- 表面被动化对于稳定QD和控制其性能至关重要.
- 连接物交换是修改QD表面化学和特性的一种常见策略.
研究的目的:
- 研究化 (CdSe) 和硫化 (CdS) 量子纳米结构上的可逆配体交换.
- 了解金属碳酸盐被动化对QD光学特性和应变状态的影响.
- 通过受控的表面修改来探索调整QD行为的潜力.
主要方法:
- 通过n-octylamine被动化的CdSe量子带与无水金属碳酸盐 (M(oleate) 2的反应,M = Cd,Zn.
- 使用光谱学和结构分析对联体交换的量子纳米结构进行表征.
- 通过将氨基连接物重新添加到金属碳酸盐被动化QD中来逆转被动化.
主要成果:
- 在CdSe和CdS QD中实现了L型胺和Z型金属碳酸盐被动化之间的快速和可逆交换.
- 金属碳酸盐被动化导致吸收和排放光谱的可逆转移到较低的能量.
- 最大的光谱转移 (140 meV) 观察到CdSe量子带被Cd (酸) 受体化,这是由于应变和封闭的变化.
- 添加Cd(oleate) 2将QD的有效厚度增加了大约一半的单层.
结论:
- 可逆连接物交换为调整CdSe和CdS量子纳米结构的光学特性提供了一个简单的途径.
- 金属碳酸盐被动化显著影响QD应变状态和封闭尺寸,导致光谱转移.
- 这项工作展示了一种可控制的方法来修改QD表面化学和光电子行为.
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