RUI: Mesoscale Methods for Electrochemistry: Confronting the Complexity of Ion and Electron Transfer

RUI：电化学的介观方法：面对离子和电子转移的复杂性

• 批准号: 1900423
• 负责人: Kevin Minbiole
• 金额: $ 34.77万
• 依托单位: Villanova University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-08-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1900423&HistoricalAwards=false
• 关键词: RUI; Mesoscale; Methods; Electrochemistry; Confronting

Project AbstractProfessor Ryan Jorn of Villanova University is supported by an award from the Chemical Theory, Models, and Computational Methods program in the Division of Chemistry. Professor Jorn develops methods to study the transport of electrons and ions at electrode surfaces, with particular focus on the reactive interfaces present in rechargeable batteries. While rechargeable batteries are essential to powering personal electronics, they may also play a significant role in reducing carbon emissions by powering cars. Several technical challenges to energy storage for transportation remain, including loss of storage capacity over time and poor rates of recharge. These challenges are intimately connected to the transport of ions and electrons at the molecular level. Unfortunately, charge transport mechanisms are poorly understood. Few experiments can access sufficiently small length and time scales at the electrode surface. Most computer simulations are also inadequate to describe the multiple length scales at work during battery operation. Studying the behavior of electrons requires using quantum mechanics to properly treat their wave-like nature. Such calculations, however, are only feasible for a relatively small numbers of atoms. Accurately capturing the evolution of the interface through which the electron travels requires accounting for thousands of atoms for very long times. Professor Jorn's research uses a multi-scale approach to study these problems. He and his coworkers compute molecular forces from quantum mechanics. They then use these forces to describe the classical motion of ions and molecules at the electrode surface. His work at Villanova University relies heavily on the involvement of undergraduate students who are trained on state-of-the-art simulation software and high-performance computing platforms. Professor Jorn also uses his research to introduce first generation and under-represented college students to computational modeling through the Center for Access, Success, and Advancement at Villanova University. Molecular simulations of electrochemical interfaces have previously relied on ab initio molecular dynamics (AIMD) to study chemical reactions, and classical molecular dynamics (CMD) to explore solvation phenomena. Regarding the former, limitations on the time scales of simulation render description of transport phenomena intractable. On the other hand, it is widely recognized that "off-the-shelf" force fields used in CMD fail to accurately capture polarization effects and interface structure. Professor Jorn's research addresses these deficiencies by employing a force-matching approach that uses information from quantum AIMD simulations to train classical molecular force fields. His research group explores how best to build force fields at interfaces by exploring different functional forms for intermolecular interactions and sampling high-energy configurations. In addition to developing force fields for interfacial processes, Professor Jorn's work includes developing enhanced sampling methods to describe the exchange of species across the electrolyte/electrode interface. By using a unique combination of replica exchange umbrella sampling and collective variables, his approach allows for the study of single defect migration as well as correlated mechanisms involving ion "knock-off". Regarding the motion of electrons, Professor Jorn's work employs a Newns-Anderson Hamiltonian coupled with ensemble scattering theory to describe the classical force on molecules during reduction. In adding electron transfer to classical simulations, Professor Jorn is developing a framework to study electrochemistry at a molecular level.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.

Villanova大学的Project Abstract Professor Ryan Jorn得到了化学理论，模型和计算方法计划的奖项的支持。 Jorn教授开发了研究电子和离子在电极表面的运输的方法，特别关注可充电电池中存在的反应性接口。 虽然可充电电池对于为个人电子设备供电至关重要，但它们也可能在减少汽车供电碳排放方面发挥重要作用。 存储能源的几个技术挑战仍然存在，包括随着时间的推移损失存储容量和充电率较差。 这些挑战与分子水平的离子和电子的运输密切相关。 不幸的是，电荷运输机制知之甚少。 很少有实验可以在电极表面访问足够小的长度和时间尺度。 大多数计算机模拟也不足以描述电池操作过程中工作中的多个长度尺度。 研究电子的行为需要使用量子力学才能正确处理其波浪样性质。 但是，这种计算仅对于相对较少的原子可行。 准确地捕获电子传播的界面的演变，需要很长时间考虑数千个原子。 杰恩教授的研究使用多尺度方法来研究这些问题。 他和他的同事通过量子力学计算分子力。 然后，他们使用这些力来描述离子和分子在电极表面的经典运动。 他在维拉诺瓦大学（Villanova University）的工作在很大程度上依赖于接受过最先进的模拟软件和高性能计算平台培训的本科生的参与。 杰恩教授还利用他的研究介绍了第一代和代表性不足的大学生，通过维拉诺瓦大学的访问，成功和进步中心进行计算建模。电化学界面的分子模拟先前依赖于从头算分子动力学（AIMD）来研究化学反应和经典分子动力学（CMD）来探索溶剂化现象。 关于前者，对模拟时间尺度的局限性渲染了传输现象的描述。 另一方面，广泛认识到CMD中使用的“现成”力场无法准确捕获极化效应和界面结构。杰恩教授的研究通过采用力量匹配方法来解决这些缺陷，该方法使用量子AIMD模拟的信息来训练经典的分子力场。 他的研究小组探索了如何通过探索不同分子间相互作用和对高能配置的不同功能形式来最好地在界面上建立力场。 除了开发界面过程的力场外，杰恩教授的工作还包括开发增强的抽样方法来描述在电解质/电极界面上的物种交换。 通过使用副本交换伞采样和集体变量的独特组合，他的方法可以研究单个缺陷迁移以及涉及离子“仿制”的相关机制。 关于电子的运动，杰恩教授的作品采用了纽恩斯·安德森汉密尔顿人，再加上合奏散射理论，以描述还原过程中分子的经典力量。 在将电子转移添加到经典模拟中时，Jorn教授正在开发一个以分子级别研究电化学的框架。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子和更广泛影响的评估来评估的支持标准。

项目成果

Ion Association and Electrolyte Structure at Surface Films in Lithium-Ion Batteries

锂离子电池表面膜的离子缔合和电解质结构

• DOI: 10.1021/acs.jpcc.1c00393
• 发表时间: 2021
• 期刊: The Journal of Physical Chemistry C
• 作者: Pinca, Justin R.;Duborg, William G.;Jorn, Ryan
• 通讯作者: Jorn, Ryan

Investigating the Mechanism of Lithium Transport at Solid Electrolyte Interphases

• DOI: 10.1021/acs.jpcc.0c03018
• 发表时间: 2020-07-30
• 期刊: JOURNAL OF PHYSICAL CHEMISTRY C
• 影响因子: 3.7
• 作者: Jorn, Ryan;Raguette, Lauren;Peart, Shaniya
• 通讯作者: Peart, Shaniya