1至2纳米直径的电子结构芯/外纳米晶体:表面化学,光学光谱,电荷转移和兴奋剂
Zhiyong Zhou1, Richard A Friesner, Louis Brus
1Chemistry Department, Columbia University, New York, NY 10027, USA.
Journal of the American Chemical Society
|December 11, 2003
概括
我们使用密度函数计算来探索纳米晶体 (SiNCs). 不同的表面被动化方法和兴奋剂显著改变了它们的电子和光学特性,偏离了简单的量子尺寸效应.
科学领域:
- 计算材料科学科学 计算材料科学
- 纳米科学和纳米技术
- 量子化学 是一个量子化学.
背景情况:
- 纳米晶体 (SiNCs) 呈现量子封闭效应,影响其电子和光学性能.
- 表面被动化对于稳定SiNC和调整它们的行为至关重要.
- 了解SiNC中的兴奋剂对于其在电子领域的应用至关重要.
研究的目的:
- 调查各种表面被动化方案 (F,H,氧化物,) 对SiNCs的影响.
- 预测被动化对最高占有分子轨道 (HOMO),最低不占有分子轨道 (LUMO),光学光谱和电子转移的影响.
- 通过使用杂质原子 (Al,P) 在量子受限SiNC中探索电.
主要方法:
- 使用了静态和时间依赖的密度函数计算 (DFT).
- 对SiNC进行了几何优化和全电子计算,最高为Si(87) H(76).
- 电子阴性比较被用来分析从量子尺寸效应模型的偏差.
主要成果:
- 不同的sp(3) 被动化方案 (F,H,氧化物,) 显著改变HOMO,LUMO和SiNCs的光学光谱.
- 电子阴性差异解释了与标准量子大小效应的偏差.
- 在表面和内部的 (Al) 和 (P) 兴奋剂中,研究了电气兴奋剂效应.
结论:
- 表面被动化策略极大地影响了纳米晶体的电子和光学特性.
- 用像P这样的杂质原子进行兴奋剂使量子受限SiNCs中的电修饰成为可能.
- 表面悬挂的键可以与多邦电子相互作用,促进内部电荷转移.
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