Understanding Ion Solvation Structure and Transport in Multicomponent Ionic Liquids

离子液体是一种液体盐混合物，具有良好的物理性质，如热稳定性和电化学稳定性、不可燃性和低挥发性，这使得它们在各种化学合成和储能应用中成为理想的溶剂、催化剂和电解液。目前的一项研究需要使电动汽车得到更广泛的采用，即具有足够耐用性的高性能电池，同时保持安全运行。这项基础研究项目旨在介绍一种控制旋钮，用于设计离子液体作为锂离子和锂金属电池电解液的性能。这种合理的设计方法可能导致实现使用不可燃电解液的更安全的电池，该电池可以在传统电解液范围之外的温度下操作，并在所有其他电解液都失效的极端还原或氧化环境中运行。该项目将推动下一代储能设备的发展。作为该项目的一部分，综合教育计划“STEAM for Energy”将通过视觉艺术镜头教授基本物理现象，从而加强学生的科学和工程训练。视觉艺术模块将通过调查人员与克利夫兰艺术学院的持续合作，被整合到凯斯西储大学的课程中。教育和推广活动的预期结果是提高对STEM的兴趣和更广泛的参与，并增强工科学生的创造力和科学交流技能。本项目的目标是了解溶质离子在多组分离子液体中的溶剂化结构和传输机制，其中存在三个或更多的离子。这项研究将利用理论指导的实验方法，将量子计算与拉曼光谱相结合来解释复杂电解液中的离子配位和溶剂化结构。将通过锂离子迁移测量和速率-性能测试来研究该结构如何影响传输特性以及最终的系统级性能。所获得的新知识将回答重要的基本问题，包括溶质离子浓度、溶剂化结构内的离子配位和多组分离子液体混合物中离子电导率之间的关系，以及离子液体的诱导、极性-非极性、纳米尺度的非均质性在决定宏观电导率和溶质离子迁移中的作用的表征和机理。这项研究将产生新的电解液和与下一代电化学能量存储系统相关的传输特性的基础。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Ionic liquids are liquid salt mixtures that have favorable physical properties such as thermal and electrochemical stability, non-flammability, and low volatility, which render them as ideal solvents, catalysts, and electrolytes in various chemical synthesis and energy storage applications. A current research need to enable wider adoption of electric cars, is high performance batteries with sufficient durability while retaining safe operations. This fundamental research project aims to introduce a control knob for the design of ionic liquids' properties as electrolytes for lithium ion and lithium metal batteries. This rational design approach may lead to the realization of safer batteries with nonflammable electrolytes operable at temperatures beyond the range of traditional electrolytes and within extremely reductive or oxidative environments where all other electrolytes fail. This project will advance the next generation of energy storage devices. As part of this project, the integrated education program 'STEAM for Energy' will enhance students' science and engineering training by teaching fundamental physical phenomena through a visual arts lens. The visual arts module will be integrated into the Case Western Reserve University curriculum through the investigators ongoing collaborations with the Cleveland Institute of Art. The expected outcomes from the educational and outreach activities are increased interest and broadened participation in STEM, and enhanced creativity and scientific communication skills for engineering students.The objective of this project is to understand the solvation structure and transport mechanism of solute ions in multicomponent ionic liquids, where ions of three or more are present. The research will utilize a theory-guided experimental approach that combines quantum calculations with Raman spectroscopy to interpret the ion coordination and solvation structure in the complex electrolytes. How the structure impacts transport properties and ultimately the system level performances will be investigated by lithium ion transference measurements and rate-capability tests. The new knowledge gained will answer important fundamental questions including the relationship among the solute ion concentration, ion coordination within the solvation structure, and the ion conductivity in multicomponent ionic liquid mixtures and the characterization and mechanism of the role of induced, polar-nonpolar, nanoscale heterogeneity of ionic liquids in determining the macroscopic conductivity and the solute ion transference. This research will produce new electrolytes and the underpinnings of the transport properties that are relevant to next generation electrochemical energy storage systems.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.