Collaborative Research: Multiscale atomistic modeling tools for electrocatalytic systems

摘要合作提案#1264104-Susan B。Sinnott #1263951-Michael J. Janik科学功绩：随着传统化石燃料能源的枯竭，需要新的能源转换和化学储能方法来为便携式和固定式应用提供能源。 燃料电池提供化学能到电能的有效转换。 电解应用逆转了这一过程，并以化学形式储存来自可再生能源（如风能或太阳能）的电力供日后使用。 能量在化学形式和电形式之间的转换效率由在装置电极处发生的原子过程决定。这些过程很难用常规实验来探测。这些过程的表征可以使用原子和量子水平的计算方法来实现。目前的建模方法用于评估电极表面的反应性有两个主要的限制：无法估计电子转移反应的速率，以及缺乏可以描述化学反应和电荷转移的原子力场，但仍保留捕获相关界面现象所需的厚度。宾夕法尼亚州立大学的Michael Janik和Janna Maranas教授以及佛罗里达大学的Susan Sinnott教授获得了国家科学基金会催化生物催化计划的奖项，以解决这些限制。&第一个限制将通过开发一个可转移的方法，电子转移速率常数使用基于量子力学的方法来解决。 该方法将应用于二氧化碳还原反应（与将电能和废二氧化碳转化为化学燃料相关）和氧还原反应（与燃料电池相关）的实验数据并进行验证。 该方法将进一步应用，与实验合作，以评估在电催化合成高价值的化学品从生物衍生的原料的反应机理。 第二个限制将解决通过一个反应分子力场与可变的部分电荷的电极和溶剂。 将为与碱金属氢氧化物电解质接触的铜和铂电极开发电荷优化的多体反应电位。 分子动力学计算将评估电化学界面，包括溶剂结构和电荷分布。 这些多尺度原子建模工具使电化学反应机制的明确识别。他们将被应用到三个具体的电催化应用，以评估一系列的反应具体的假设。更广泛的影响：这项工作的广泛影响确保了清洁能源的未来，可再生能源和化学能源储存共同努力，为可持续能源提供了一种有效，实用的方法。该项目开发了一个联合量子化学和反应分子动力学框架来模拟电化学界面，促进改进电池，燃料电池和电网级电化学储能材料的合理设计。 考虑到这一点，教育活动旨在激励学生追求能源相关领域的职业生涯。 研究生将受益于两所大学的跨学科研究项目，并熟练掌握多种计算机模拟方法。 部分拟议的工作将被打包为宾夕法尼亚州立大学和佛罗里达大学的本科项目，包括通过宾夕法尼亚州立大学少数民族本科生研究经验和妇女在科学和工程研究计划代表性不足的群体。 研究机会将提供给高中学生通过美国。来自佛罗里达。 开发的计算机模拟方法将广泛分布到计算社区，允许其他人将开发的技术应用于本提案范围之外的电化学问题。

ABSTRACTCollaborative Proposals #1264104 - Susan B. Sinnott #1263951 - Michael J. Janik Scientific Merit: As traditional fossil fuel sources of energy are depleted, new energy conversion and chemical energy storage approaches will be needed to supply energy for both portable and stationary applications. Fuel cells offer efficient conversion of chemical to electrical energy. Electrolysis applications reverse this process and store electricity from renewable sources, such as the wind or sun, in chemical form for later use. The efficiency of converting energy between chemical and electrical forms is dictated by atomistic processes that occur at device electrodes. These processes are difficult to probe with conventional experiments. The characterization of these processes is enabled using atomic and quantum level computational methods. There are two major limitations in current modeling approaches for evaluating reactivity of electrode surfaces: the inability to estimate rates for electron transfer reactions and the lack of atomistic force fields that can describe chemical reactions and charge transfer, yet retain the thickness required to capture relevant interfacial phenomena. Professors Michael Janik and Janna Maranas of Pennsylvania State University and Susan Sinnott of the University of Florida have received an award from the National Science Foundation Catalysis & Biocatalysis Program to tackle these limitations. The first limitation will be addressed through the development of a transferable method for electron transfer rate constants using methods based on quantum mechanics. This method will be applied and validated versus experimental data for the carbon dioxide reduction reaction (of relevance for converting electrical energy and waste carbon dioxide into a chemical fuel) and the oxygen reduction reaction (of relevance in fuel cells). The method will be further applied, in collaboration with experiment, to evaluate the reaction mechanism in the electrocatalytic synthesis of high value chemicals from bio-derived feedstock. The second limitation will be addressed through a reactive molecular force field with variable partial charges for both electrode and solvent. Charge optimized many-body reactive potentials will be developed for copper and platinum electrodes in contact with alkali hydroxide electrolytes. Molecular dynamics calculations will evaluate electrochemical interface, including solvent structure and charge distribution. These multiscale atomistic modeling tools enable definitive identification of electrochemical reaction mechanisms. They will be applied to three specific electrocatalytic applications to evaluate a series of reaction specific hypotheses. Broader Impacts: The broader impacts of this work secure a clean energy future in which renewable energy and chemical energy storage work together to provide an efficient, practical approach to sustainable energy. This project develops a joint quantum chemistry and reactive molecular dynamics framework to model electrochemical interfaces, facilitating rational design of materials for improved batteries, fuel cells, and grid-level electrochemical energy storage. With this in mind, educational activities are designed to motivate students to pursue careers in energy related fields. Graduate students will benefit from an inter-disciplinary research project at two universities, and become skilled in multiple computer simulation methods. Portions of the proposed work will be packaged as undergraduate projects at both Penn State and the University of Florida, including underrepresented groups through the Penn State Minority Undergraduate Research Experience and Women in Science and Engineering Research programs. Research opportunities will be provided to high school students through the U. of Florida. The developed computer simulation methods will be broadly distributed to the computational community, allowing others to apply the techniques developed to electrochemical problems outside the scope of this proposal.