单壁碳纳米管在强酸中的同位素-阴性相过渡
Pradeep K Rai1, Robert A Pinnick, A Nicholas G Parra-Vasquez
1Carbon Nanotechnology Laboratory, Center for Nanoscale Science and Technology, Rice University, Houston, Texas 77005, USA.
Journal of the American Chemical Society
|January 13, 2006
概括
本研究量化了 Brønsted-Lowry 酸的同位相中单壁碳纳米管 (SWNT) 的最大度. 对于同位素-阴性过渡的关键度随着酸强度的增加而增加,支持侧壁质突机制.
科学领域:
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
- 纳米技术 纳米技术
背景情况:
- 单壁碳纳米管 (SWNTs) 可以在溶液中形成液晶相.
- 了解SWNT在酸性介质中的相位行为对于其处理和应用至关重要.
- 布伦斯特德 - 劳里酸是有效的溶剂,可以通过侧壁质突分散SWNT.
研究的目的:
- 量化确定布伦斯特德 - 劳里酸的同位素相中的SWNTs的最大度.
- 为了确定SWNT在强酸中的同位素-阴性相过渡的临界度.
- 为了研究酸强度和这个临界度之间的关系.
主要方法:
- 使用离心技术来分离SWNT分散的同otropic和nematic相.
- 采用紫外线与近红外线 (nIR) 光谱法来量化SWNT度.
- 建立了超酸性 (400-1400 nm范围) 中的SWNTs的酒法规校准曲线.
主要成果:
- 成功量化了在同位素相 (Cmax) 中SWNT的最大度.
- 证明Cmax代表了同位素-阴性过渡的临界度.
- 在超酸盐中观察到SWNT度和200ppm以下的吸收率之间的线性关系.
- 发现临界度随着酸强度的增加而增加.
结论:
- 该研究提供了SWNT在酸中的同位素相极限的第一次定量评估.
- 这些发现支持侧壁质突机制作为SWNT在酸中分散的基础.
- 结果为控制SWNT液晶形成和处理提供了有价值的数据.
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