单一合金化物集群连接点的行为
Brycelyn M Boardman1, Jonathan R Widawsky, Young S Park
1Department of Chemistry, Columbia University, New York, New York 10027, USA.
Journal of the American Chemical Society
|May 5, 2011
概括
研究人员测量了石素化集群的电导率. -硫化团表现出最高导电,而-硫化团显示出最低导电,与理论预测保持一致.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 量子化学 是一个量子化学.
背景情况:
- 半导体量子点的电性能很难确定,因为大小/组成的变化和连接体/电极结合的复杂性.
- 探测电导需要单点/集群层次的测量,特别是关于联体/电极相互作用.
研究的目的:
- 为了研究石素化集群 (Co-Te,Co-Se,Co-S) 的电导性能.
- 为了将导电量与联体/电极结合和电子结构相关联.
主要方法:
- 使用扫描道显微镜 (STM) 进行基于断裂结的测量.
- 循环电压测量和密度函数理论 (DFT) 的计算用于比较.
主要成果:
- 观察到一个明确的导电性趋势:Co-Te集群的导电性最高,其次是Co-Se,然后是Co-S集群的导电性最低.
- 这些实验发现与氧化潜力和DFT计算的HOMO-LUMO差距的循环电压测量数据强烈一致.
结论:
- 这项研究成功地描述了石素化集群的电导率.
- 导电可以根据石化化合物组成调节,为量子点设备工程提供了洞察力.
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