使用固体支催化剂培养的单壁碳纳米管的狭窄 (n,m) 分布
Sergei M Bachilo1, Leandro Balzano, Jose E Herrera
1School of Chemical Engineering and Materials Science, University of Oklahoma, 100 East Boyd Street, Norman, Oklahoma 73019, USA.
Journal of the American Chemical Society
|October 14, 2005
概括
研究人员使用一种新的化学蒸气沉积 (CVD) 方法实现了单壁碳纳米管 (SWNT) 的选择性生长. 该工艺主要产生特定的半导体SWNT结构 (6,5) 和 (7,5),直径可控.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 化学 化学 化学
背景情况:
- 单壁碳纳米管 (SWNTs) 的受控合成对于它们的应用至关重要.
- 现有的方法通常会产生SWNT结构的广泛分布.
- 结构选择性增长仍然是纳米管制造的重大挑战.
研究的目的:
- 开发一种化学蒸气沉积 (CVD) 方法,用于SWNTs的高度结构选择性生长.
- 为了确定由新型催化系统产生的占主导地位的SWNT结构.
- 描述合成的SWNTs的物理性质,如直径和角.
主要方法:
- 使用化学蒸汽沉积 (CVD) 技术与固体支持的催化剂.
- 作为催化剂,采用了由和 (Mo) 盐混合在现场形成的 (Co) 的支纳米集群.
- 分析纳米管产品使用光谱测量以获得详细的 (n,m) 结构分辨率.
主要成果:
- 实现了SWNTs的异常结构选择性生长.
- 确定了两个特定结构 (6,5) 和 (7,5) 主导半导体SWNT群体,占50%以上.
- 合成的SWNT的平均直径为0.81nm,并且对靠近扶手椅极限的奇拉角度有强烈的偏好.
结论:
- 开发的CVD方法与现场形成的Co-Mo纳米集群使得SWNTs的高度选择性合成成为可能.
- (6,5) 和 (7,5) 结构的主导地位表明对纳米管生长的精确控制.
- 这些发现为生产具有针对先进电子和光学应用的定制性质的SWNT铺平了道路.
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