辅溶剂对碳纳米管的水合的影响
1Department of Chemistry, P.O. Box 30012, Texas A&M University, College Station, Texas 77842, USA.
Journal of the American Chemical Society
|December 25, 2009
概括
分子动力学模拟揭示了尿素,甲醇和三甲基胺N-氧化物 (TMAO) 如何影响单壁碳纳米管 (SWNT) 内的水. 尿素增强SWNT的水分,而TMAO和甲醇减少它,影响受限水的稳定性.
科学领域:
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
- 计算化学计算化学
背景情况:
- 单壁碳纳米管 (SWNTs) 由于其结构具有独特的特性.
- 了解水和辅溶剂在狭窄的纳米环境中的行为至关重要.
- 常见的生物辅溶剂对SWNT水化的影响仍然是活跃的研究领域.
研究的目的:
- 为了研究尿素,甲醇和三甲基胺N-氧化物 (TMAO) 对非极性SWNT内部水分的作用.
- 阐明辅溶剂特性在调节SWNT孔内水的行为中的作用.
- 分析控制受限水的稳定性的相互作用能量.
主要方法:
- 用分子动力学 (MD) 模拟来建模在水溶液中溶解的非极性SWNT.
- SWNT的尺寸是特别选择,允许水,但不是辅助溶剂透到内部.
- 分析的重点是水合水平,相互作用能量以及静电力和范德瓦尔斯力的贡献.
主要成果:
- 发现蛋白质变质剂尿素可以改善SWNT内部的水分.
- 三甲基胺N氧化物 (TMAO),一种蛋白质保护剂,以及甲醇导致SWNT内部脱水.
- 限制在SWNT孔内的水的稳定性主要由TMAO和甲醇溶液中的静电相互作用来决定,而静电和范德瓦尔斯相互作用在尿素溶液中都很重要.
结论:
- 辅溶剂显著改变 SWNT 内的水的水合状态.
- 观察到的效应与已知辅溶剂的蛋白质稳定或变性特性相关.
- 这些发现突出了静电和范德瓦尔斯相互作用在确定纳米材料内封闭的水溶液稳定性的重要性.
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