在压缩金属纳米晶体中共存,竞争道和跳动电荷传输
Shiyu Ji1,2, Di Peng1,2, Fang Sun3
1Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, Hefei 230031, P. R. China.
Journal of the American Chemical Society
|October 30, 2023
概括
原子精确的金纳米集群通过精确控制粒子间距离,表现出与大量银相比的导电性. 这项研究推进了金属纳米半导体,为传统,不太稳定的材料提供了替代品.
科学领域:
- 材料科学
- 纳米技术
- 固态物理
背景情况:
- 超小的金属纳米粒子 (∼1 nm) 在理解电荷传输方面存在挑战.
- 传统的半导体 (<10 nm) 通常是绝缘和不稳定的.
- 原子精确的金纳米集群为先进材料提供可调节的特性.
研究的目的:
- 在金纳米团固体中建立导电性和粒子间距离之间的数学关系.
- 研究这些新材料中的电荷传输机制.
- 推进基于金属纳米集群的半导体的开发.
主要方法:
- 在现场高压电阻的表征.
- 同步射线射线衍射 (XRD).
- 状态和Hall测量的Murnaghan方程.
主要成果:
- 导电性与粒子间距离之间确立了精确的相关性.
- 预测的Au25 ((SNap) 18) 固体的导电性与散装银相比,其粒子间距离为3.6 Å.
- 确定了共存的道和不连贯的跳动电荷传输机制.
结论:
- 调整连接体结构,纳米集群架构和应用高压可以提高导电性.
- 确定了载荷类型,从而对运输提供了更深入的见解.
- 这项工作是金属纳米半导体研究的重大进展.
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