在以为基础的微孔金属有机框架中依赖于阴离子的内在电导率
Sarah S Park1, Eric R Hontz, Lei Sun
1Department of Chemistry, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
Journal of the American Chemical Society
|January 20, 2015
概括
研究人员发现,通过控制S·S相互作用,可以设计具有可调节电导性的金属有机框架 (MOF). 这些MOF中较大的金属离子缩短了S·S接触,提高了先进电子材料的导电性.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 纳米技术 纳米技术
背景情况:
- 金属有机框架 (MOF) 是具有可调节结构的多孔材料.
- MOF中的电导率是电子应用的活跃研究领域.
- 控制MOF中的电荷传输对于开发先进材料至关重要.
研究的目的:
- 研究同结构MOF中的晶体结构和电导率之间的关系.
- 了解金属离子大小如何影响电荷传输通路.
- 通过结构修改来证明MOF中的调节导电性.
主要方法:
- 同结构MOF与不同金属离子 (Mn,Co,Zn,Cd) 和四亚富四酸连接体的合成.
- 单晶导电性测量. 一个晶体的导电性测量.
- 密度函数理论 (DFT) 计算分析电子结构和轨道相互作用.
主要成果:
- 在单晶导电性和TTF芯之间最短的S·S相互作用距离之间发现了直接的相关性.
- 较大的金属离子导致较短的S··S接触,改善轨道重叠.
- (Cd) 模拟物表现出最高导电率 (2.86 × 10−4 S/cm),这是由于最短的S··S接触.
- DFT计算证实了S·S相互作用在价值带和导电性中的作用.
结论:
- 该研究表明,在同结构MOF中可调节的内在电导率.
- 金属离子的大小是调节S·S相互作用和电荷传输的关键因素.
- 这些发现为设计用于电子应用的可控导电的MOF提供了蓝图.
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