Modeling electrocatalysts in operating conditions: Surface restructuring and catalytic activity

模拟运行条件下的电催化剂：表面重组和催化活性

• 批准号: 2103116
• 负责人: Philippe Sautet
• 金额: $ 50.21万
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2103116&HistoricalAwards=false
• 关键词: Modeling; electrocatalysts; operating; conditions; Surface; Modeling; electrocatalysts; operating; conditions; Surface

Electrochemistry is slated to play a large role in clean energy, chemical manufacturing, and environmental processes in coming years, as renewable electricity becomes increasingly available from sources such as wind and solar energy. The project focuses on two electrochemical reactions, the hydrogen evolution reaction (HER) to produce hydrogen from water, and the carbon dioxide reduction reaction (CO2RR) to convert CO2 to higher-value products. Both reactions are facilitated by catalysts. Copper-based catalysts are amongst the most active identified to date, but as with many electrocatalysts, their chemical structure changes under reaction conditions. The project focuses on understanding the reconstruction process with the goal of designing more active, selective, and stable catalysts. Specifically, the project develops and employs computational techniques to predict structural changes in response to key electrochemical process variables. Beyond the technical aspects, the project incorporates a training program for high-school teachers that brings the topics of sustainability and energy to their classrooms, while introducing students to the rapidly emerging area of molecular modeling. The project will determine, by unique first-principles, multi-scale stochastic theoretical simulations, how the surface of copper-based electrocatalysts used for the hydrogen evolution and CO2 electroreduction reactions restructures in realistic conditions of potential, solvent, and electrolyte. The influence of the potential-induced reconstruction on the electrocatalytic mechanism, activity, and selectivity of these reactions will be studied, in link with experiments. There is evidence from in-situ characterization that the surface structure of electrocatalysts is strongly modified in operational conditions. However, it is not yet possible to determine the atomic structure of the active surface, and thus, the implications of these reconstructions on the mechanisms are unknown. The proposed multiscale first-principle simulations appear to be the most adequate approach to elucidate the interface structure. Principally, new reaction mechanisms may emerge. The selectivity of CO2 electroreduction versus hydrogen evolution (the latter being a major hurdle in applications) will be studied. Several theoretical methods unique to the laboratories of the PIs, including the incorporation of electrochemical potential, solvent effects, global optimization algorithms, and STM image simulations, will be advanced, adapted, and merged to make this research possible. Close connection to the experiment is proposed, both for structural aspects, with operando scanning tunneling microscopy (STM), and to validate the predicted kinetics and selectivity. This project will educate young researchers in techniques of modern surface chemistry and catalysis, including realistic modeling, method development, quantum mechanics, and statistical mechanics. In addition, students will learn how to connect modeling efforts to experimental data and capabilities. The training will promote a highly-skilled workforce to address global challenges in the manufacture of sustainable fuels and chemicals.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.

随着可再生能源从风能和太阳能等来源越来越多，电化学计划在未来几年的清洁能源，化学制造和环境过程中发挥重要作用。 该项目着重于两种电化学反应，即从水中产生氢的氢反应（HER），以及二氧化碳还原反应（CO2RR），以将CO2转换为高价值产物。 两种反应均由催化剂促进。 基于铜的催化剂是迄今为止确定的最活跃的催化剂之一，但是与许多电催化剂一样，它们的化学结构在反应条件下发生了变化。 该项目的重点是理解重建过程，目的是设计更活跃，选择性和稳定的催化剂。具体而言，该项目开发并采用计算技术来预测响应关键电化学过程变量的结构变化。 除了技术方面，该项目还纳入了一项针对高中老师的培训计划，该计划将可持续性和能源的主题带到了教室，同时向学生介绍了分子建模的快速新兴领域。该项目将通过唯一的第一原理，多尺度的随机理论模拟来确定基于氢化的氢的电催化剂表面如何在现实，溶剂和电解质的现实条件下进行氢气进化和CO2电化反应重组。潜在诱导的重建对这些反应的电催化机制，活性和选择性的影响将与实验联系起来。有证据表明，电催化剂的表面结构在操作条件下得到了强烈的修饰。 但是，尚不可能确定活性表面的原子结构，因此，这些重建对机制的含义尚不清楚。提出的多尺度第一原则模拟似乎是阐明界面结构的最适当方法。 主要是，新的反应机制可能会出现。将研究二氧化碳电力与氢化的选择性（后者是应用中的主要障碍）。 PIS实验室所独有的几种理论方法，包括将电化学潜力，溶剂效应，全球优化算法和STM图像模拟的结合纳入，将进行提前，适应和合并以使这项研究成为可能。提出了与实验的紧密连接，包括结构性方面，操作扫描隧道显微镜（STM），并验证预测的动力学和选择性。该项目将教育年轻的研究人员有关现代表面化学和催化技术的技术，包括现实的建模，方法开发，量子力学和统计力学。此外，学生将学习如何将建模工作与实验数据和功能联系起来。该培训将促进高技能的劳动力，以应对制造可持续燃料和化学物质的全球挑战。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智力优点和更广泛的审查标准来评估的。