通过耗尽介导的体系统的相位图的直接确定
Sanghyuk Park1, Hyerim Hwang2, Shin-Hyun Kim1
1Department of Chemical and Biomolecular Engineering and KAIST Institute for the NanoCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea.
Journal of the American Chemical Society
|September 28, 2022
概括
这项研究实验性地研究了水性悬浮液中耗尽介导的合相行为. 研究人员通过控制消耗剂和盐度来确定不同的液体,晶体和玻璃相,揭示了相变的关键参数.
科学领域:
- 体和表面科学
- 软物质物理学
- 材料科学
背景情况:
- 耗尽相互作用对于调节体行为至关重要,使各种晶体和玻璃相成为可能.
- 之前对水性悬浮体中耗尽介导相位行为的实验研究是有限的.
- 了解这些相互作用是控制合体自组合的关键.
研究的目的:
- 通过耗尽相互作用在水性合物悬浮中实验实施和研究流体,晶体和玻璃相.
- 通过计算对电位来确定流体和晶体相之间的相界.
- 根据组装速度和对潜在的斜率来描述玻璃形成的开始.
主要方法:
- 使用各种消耗剂和盐度的聚乙烯颗粒的水性悬浮剂.
- 通过组合范德瓦尔斯,静电和耗尽相互作用来计算对潜力.
- 从反射光谱中确定了未知的参数 (离子杂质度,耗耗与度比).
- 从晶体阶段的布拉格衍射峰值中提取了粒子间距.
- 估计来自对潜在斜率的组装速度来描述玻璃形成.
主要成果:
- 成功实现了三个不同的阶段:流体,晶体和玻璃.
- 定义了3kBT的能量井深度的流体晶体边界.
- 确定玻璃形成的特点是组装速率 (超过300微米/秒),而不是井深.
- 证明晶体是通过度增长形成的,而玻璃则是通过快速阻塞形成的.
结论:
- 耗尽相互作用为控制水系统中的合相行为提供了一种通用方法.
- 这项研究为合相过渡的理论模型提供了实验验证.
- 区分结晶的热力学控制和体系统中的玻璃形成的运动控制.
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