水和乙醇在石墨烯氧化物中的扩散动力学
Gobin Raj Acharya1, Madhusudan Tyagi2,3, Eugene Mamontov4
1Department of Physics and Astronomy, Wayne State University, Detroit, Michigan 48201, United States.
The journal of physical chemistry. B
|August 9, 2023
概括
在石墨烯氧化物中被封闭的水和乙醇显示运动减少和动态变化. 它们的扩散速度较慢,观察到不同的移动和不移动分数,影响它们在不同温度下的行为.
科学领域:
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
- 化学物理 化学物理
背景情况:
- 了解多孔纳米材料中的液体行为对于应用至关重要.
- 氧化石墨烯 (GO) 具有独特的表面化学和封闭效应.
- 在封闭系统中探测分子动力学需要先进的技术.
研究的目的:
- 为了研究水和乙醇在石墨烯氧化物中的动态.
- 为了确定温度和方向对受限液体行为的影响.
- 描述受限分子的扩散机制和分数.
主要方法:
- 准弹性中子散射 (QENS) 使用动量转移 (Q) 的依赖性.
- 在不同温度下对GO粉末和膜进行的实验.
- 测量 anisotropy 测试方向动力学.
主要成果:
- 对水 (高达30%) 和乙醇均观察到减少的扩散性.
- 在封闭液体中压缩动态过渡温度.
- 有证据表明,静止和移动分数具有跳跃扩散动态.
结论:
- 封闭在GO中显著改变了水和乙醇的动态.
- 跳跃扩散长度与GO表面结构相关.
- 微弱的异构性表明分子运动的方向偏好有限.
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