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Preparation of Carbon Nanosheets at Room Temperature
Published on: March 8, 2016
CH4分子组合的异常局限于单壁碳纳米角空间
Sachie Hashimoto1, Toshihiko Fujimori, Hideki Tanaka
1Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan.
Journal of the American Chemical Society
|February 2, 2011
概括
在低温下,单壁碳纳米角内甲 (CH4) 旋转受到高度限制. 这种限制导致了刚性结构,与其在散装液体阶段的行为不同.
科学领域:
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
- 频谱学是一种光谱学.
背景情况:
- 了解狭窄环境中的分子行为对于纳米材料应用至关重要.
- 在纳米孔状材料中的甲 (CH4) 吸附会影响其物理和化学性质.
- 单壁碳纳米角 (SWCNHs) 为分子限制研究提供了独特的纳米空间.
研究的目的:
- 为了研究SWCNH中吸附的甲 (CH4) 的振动旋转特性.
- 为了确定纳米限制对甲分子动态的影响.
- 为了比较封闭的甲与其散装气体和液体相的行为.
主要方法:
- 红外 (IR) 光谱学被用来研究在SWCNHs上吸附的CH4.
- 测量是在105K至140K的温度下进行的.
- 分析的重点是v3和v4的振动模式及其旋转带结构.
主要成果:
- 在130K以下,v3和v4波段的P和R分支被抑制.
- 与气相相比,Q分支仍然可以观察到,其宽度明显较窄.
- 更窄的Q分支表明由于运动受限而导致多普勒效应的抑制.
结论:
- 在SWCNHs的纳米空间内,甲旋转受到高度限制.
- 封闭的甲形成了一个刚性的组装结构.
- 这种行为与大量液态相中的甲相比异常,突出显示了独特的限制效应.
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