在疏水性二氧化纳米管中观察毛细体
Karthik Jayaraman1, Kenji Okamoto, Sang Jun Son
1Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, USA.
Journal of the American Chemical Society
|December 8, 2005
概括
溶剂在疏水性氧化纳米管中表现出独特的湿行为,与宏观预测不同. 这项研究揭示了湿的急剧,可逆转变,挑战了纳米尺度的传统毛细血管理论.
科学领域:
- 纳米技术纳米技术
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
背景情况:
- 模板合成的纳米管提供可调节的纳米容器,用于研究受限液体.
- 了解纳米孔中的溶剂行为对于各种应用至关重要.
研究的目的:
- 为了研究疏水性氧化纳米管内部的湿透性.
- 将纳米级湿现象与宏观毛细体理论进行比较,特别是扬-拉普拉斯方程.
主要方法:
- 对内部直径为30nm和170nm的单个二氧化纳米管的实验研究.
- 在一系列条件下使用水/甲醇混合物的湿的研究.
- 进行了补充组合实验.
主要成果:
- 在添加甲醇后,观察到湿和不湿状态之间的急剧过渡.
- 这种过渡在30nm和170nm纳米管中一致.
- -拉普拉斯方程未能准确预测湿过渡时的甲醇度.
- 观察到的湿行为是可逆的.
结论:
- 虽然一些方面与传统的毛细管一致,但疏水纳米管中的纳米级湿与扬-拉普拉斯的预测有所不同.
- 差异可能源于使用宏观接触角度值或孔内液相不稳定.
相关概念视频
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