在无CVD中选择性增长亚纳米直径单壁碳纳米管阵列
Lixing Kang1,2,3, Shibin Deng1, Shuchen Zhang1
1Center for Nanochemistry, Beijing Science and Engineering Center for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University , Beijing 100871, P. R. China.
Journal of the American Chemical Society
|September 23, 2016
概括
研究人员开发了一种使用固体碳化催化剂控制的小直径单壁碳纳米管 (SWNT) 阵列的方法. 这一进步对于高性能近红外光电子设备至关重要.
科学领域:
- 材料科学
- 纳米技术
- 凝聚物质物理学
背景情况:
- 单壁碳纳米管 (SWNT) 对于先进的光电子设备至关重要.
- 控制SWNT直径和度是优化其光学和电子性能的关键.
- 具有较大的带隙的亚纳米直径SWNT特别适用于近红外应用.
研究的目的:
- 开发一种选择性增长方法,用于对齐的亚纳米直径SWNT阵列.
- 在种植的SWNT中实现狭窄的性分布.
- 为了提高SWNT密度,用于实际的设备制造.
主要方法:
- 使用固体碳化 (Mo2C) 催化剂进行SWNT生长.
- 在无气化学蒸汽沉积 (CVD) 环境中采用低碳养和短生长时间.
- 研究催化剂大小和回火过程对SWNT特征的作用.
- 描述SWNT的直径,密度和度分布.
主要成果:
- 成功生长了直线SWNT阵列,直径为亚纳米 (∼84%在0.75和0.95nm之间).
- 获得了狭窄的性分布,其中特定的性占主导地位 (> 73%).
- 通过操纵催化剂大小和碳养率来控制SWNT的生长.
- 在蓝宝石基板上通过化增加SWNT密度至≤15管/μm.
结论:
- 固体Mo2C催化剂可以选择性,短时间生长的亚纳米SWNT,并可控制其性.
- 该方法为特定应用量身定制SWNT特性提供了一条途径.
- 这项研究为纳米电子中的对齐SWNT的结构控制提供了宝贵的见解.
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