在近离子离子液体中,在液体-液体和液体-玻璃过渡时,电荷传输的非同步行为
1Institute of Physics, University of Silesia in Katowice, Silesian Center for Education and Interdisciplinary Research, 75 Pułku Piechoty 1A, 41-500 Chorzów, Poland.
The journal of physical chemistry. B
|May 14, 2024
概括
本研究探讨了离子液体中的液体-液体过渡 (LLT),揭示了压力.
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:
- 一个单元材料的两个液态相之间的可逆的第一阶段过渡,称为液态-液态过渡 (LLT),仍然不太了解.
- 离子液体 (ILs) 是一种具有调节性质的材料类,使其成为研究LLT等基本现象的有趣候选者.
- 选择了四基离子液体,特别是[P666,14]Cl和[P666,14][1,2,4-triazolide],是因为它们可能表现出LLT行为.
研究的目的:
- 在两个四基酸离子液体中研究液体-液体过渡 (LLT) 现象:[P666,14]Cl和[P666,14][1,2,4-triazolide].
- 探索温度和压力对LLT以及相关的电荷传输动态的影响.
- 描述在LLT过程中电荷传输的行为以及在不同压力条件下的液态玻璃过渡.
主要方法:
- 差分扫描热量计 (DSC) 用于检测与LLT相关的热事件.
- 介电光谱学被用来探测电荷传输的动态和在不同温度和压力下的结构重组.
- 进行了高压介电测量,以阐明压力在LLT和自组装过程中的作用.
主要成果:
- [P666,14]Cl和[P666,14][1,2,4-triazolide]都表现出205K以下的液体-液体过渡,从一个无序的液体 (液体1) 过渡到一个自我组装的液体 (液体2).
- 在自组装液体2中,电荷传输与结构动力学脱.
- 压力显著影响液体2的自我组织,导致压力依赖的电荷传输时间表. 在LLT中观察到电荷传输的非同步行为,压力诱导的过渡时间比大气压下更短.
- 液态玻璃过渡过程中的介电学研究表明,电荷传输时间尺度的非单调行为,对[P666.14]Cl的压力增加,而[P666.14][Trz]的时间尺度几乎不变.
结论:
- 该研究表明,在特定的离子液体中存在液体-液体过渡,突出了自我组装在形成不同的液体相中的作用.
- 压力在LLT和电荷传输动态中发挥着关键作用,与温度相比,它提供了一个不同的途径来诱导相位过渡.
- 观察到的非同时性行为和压力依赖的动态强调了离子液体中LLT的复杂性,并表明了该材料类内的多种机制.
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