在无形单层碳中调整过的导电性
Huifeng Tian1, Yinhang Ma2, Zhenjiang Li1
1School of Materials Science and Engineering, Peking University, Beijing, China.
Nature
|March 1, 2023
概括
研究人员通过控制生长温度来调整无形单层碳 (AMC) 薄膜的干扰 (DOD) 和电导率. 这将原子结构与材料特性联系起来, 使新的二维电子设备成为可能.
科学领域:
- 材料科学
- 凝聚物质物理学
- 纳米技术
背景情况:
- 由于确定3D原子位置的困难,将原子配置 (失序程度 - DOD) 与无形固体的属性相关联是具有挑战性的.
- 二维 (2D) 系统为原子成像提供了更简单的方法,有助于研究无形材料.
- 之前的研究可视化了无形单层碳 (AMC) 的原子配置,但缺乏与宏观性质的直接联系.
研究的目的:
- 在无形单层碳 (AMC) 膜中建立原子尺度结构和宏观性质之间的直接因果关系.
- 通过控制生长温度,在AMC中轻松调整混乱程度 (DOD) 和电导率.
- 开发一个框架,将微观结构参数与2D无形材料的电特性连接起来.
主要方法:
- 在不同温度下使用激光辅助沉积的无形单层碳膜 (AMC) 的生长.
- 原子分辨率电子显微镜可视化原子配置,中距离顺序 (MRO) 和纳米晶体密度.
- 数字计算以建立基于微观结构参数的导电图.
主要成果:
- 在 pyrolysis 值温度下实现了具有中距离顺序 (MRO) 的可变跳转导电 AMC.
- 增加25°C的生长温度导致MRO的损失,使AMC具有电绝缘性,板材阻力增加了10^9倍.
- 确定了两个订单参数 (MRO和纳米晶体密度的存在/不存在),以完全描述DOD.
结论:
- 这项研究成功地将原子尺度结构 (混乱程度,MRO,纳米晶体密度) 与二维无形材料的电导率联系起来.
- 增长温度被确定为调节DOD和AMC中的导电性的关键参数.
- 这项工作促进了无形材料的结构-性质关系的理解,并为二维无形电子设备开辟了道路.
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