合成不同尺寸的钻石形酸分子板,实现从二维缩小到零的量子束效应
Eunju Lee Tae1, Kee Eun Lee, Jong Seok Jeong
1Center for Microcrystal Assembly, Department of Chemistry, and Program of Integrated Biotechnology, Sogang University, Seoul 121-742, Korea.
Journal of the American Chemical Society
|April 19, 2008
概括
研究人员合成了钻石形的酸分子板,将尺寸从2D缩小到0D,没有表面连接体. 这一突破使控制的半导体纳米粒子合成具有可调节的光学特性.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 半导体物理 半导体物理
背景情况:
- 具有统一性质的半导体纳米粒子的受控合成具有挑战性.
- 在没有表面被动化的情况下实现二维分子板的尺寸缩小是一个尚未满足的需求.
研究的目的:
- 报告一个大规模的酸盐分子片的合成,其尺寸逐渐减少.
- 为了研究从2D到0D半导体纳米粒子的维度减小.
- 描述合成材料的光学和电子特性.
主要方法:
- 大规模合成0.75纳米厚的钻石形状的莱比多克罗类型的泰坦酸盐分子板.
- 从 (27.3, 19.1) nm逐渐缩小到 (7.7, 5.5) nm.
- 激子吸收带,振荡器强度,激子质量和波尔半径的表征.
主要成果:
- 在没有表面连接体的情况下,成功合成了具有减小尺寸的酸盐分子板.
- 观察了三个激电吸收带 (4.0-6.5 eV),随着板面积的减少,能量增加.
- 每个单元细胞振荡器强度随面积增加;每个粒子强度相应增加.
- 与散装泰坦酸盐相比,显著降低了平均减少的激子质量 (0.10-0.11 m e) 和波尔半径 (4.8-4.3 nm).
结论:
- 这项工作介绍了半导体纳米粒子通过从2D到0D的维度缩小在系列中的首次合成.
- 可调节的光学属性与尺寸和量子束效应有关.
- 这些发现挑战了关于纳米材料振荡器强度的现有信念.
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