Chemical Imaging of Metal Surfaces at the Solid-Liquid Interface: Effects of Grain Structure on Electrocatalytic Reactions

固液界面金属表面的化学成像：晶粒结构对电催化反应的影响

• 批准号: 2246583
• 负责人: Steven Baldelli
• 金额: $ 45.45万
• 依托单位: University of Houston
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-06-01 至 2026-05-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2246583&HistoricalAwards=false
• 关键词: Chemical; Imaging; Metal; Surfaces; Solid

With support from the Chemical Structure, Dynamics, and Mechanisms-A (CSDM-A) and the Chemical Measurement and Imaging (CMI) Programs in the Division of Chemistry, Professor Steven Baldelli from the University of Houston is using highly sensitive surface techniques to understand how molecules react on polycrystalline electrodes. Chemical reactivity of analytes adsorbed to an electrode depends on the underlying crystallinity of a surface as well as its adjacent grains. Studying these effects require the use of methods that reveal surface crystallography, depend on the electrode surface electronic state and symmetry, and impact local vibrational information about the adsorbed molecules. By controlling the system electrochemically, Professor Baldelli and his students will map surface chemistry and link it to underlying crystallography to develop a physical understanding of how crystalline domains influence heterogeneous catalysis. Graduate, undergraduate, and high school students will be mentored and collaborate through this research. Students will develop skills related to instrument building, data analysis, and spectral and microscopy image interpretation.This project uses in situ sum frequency generation vibrational spectroscopy/microscopy (SFG) to probe molecules adsorbed to an electrode while second harmonic generation microscopy (SHG) assists in the determination of the electronic state and symmetry of the electrode. Because SHG anisotropy is related to surface crystallography, the combination of these techniques results in the generation of correlated maps of surface chemistry and underlying crystallography. Surface reactivity is then interrogated using cyclic voltammetry with sub-micron resolution under reaction conditions. In so doing, impacts of adjacent grains in a polycrystalline surface are evaluated. Broader impacts of this work have the potential to advance surface sensitive spectroscopy and microscopy tools that could advance the chemical and physical understanding of how the electrode influences heterogeneous electrocatalysis.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.

在化学结构，动力学和机制-A（CSDM-A）以及化学测量和成像（CMI）计划的支持下，休斯顿大学的史蒂文·巴尔德利教授在化学划分中使用了高度敏感的表面技术来了解分子对多晶电电子的反应。吸附到电极的分析物的化学反应性取决于表面的潜在结晶度及其相邻晶粒。研究这些效果需要使用揭示表面晶体学的方法，取决于电极表面电子状态和对称性，并影响有关吸附分子的局部振动信息。通过通过电化学控制系统，Baldelli教授和他的学生将绘制表面化学的绘制，并将其与潜在的晶体学联系起来，以对晶体领域如何影响异质性催化产生物理理解。通过这项研究，将指导和协作研究生，本科和高中生。学生将开发与仪器构建，数据分析以及光谱和显微镜图像解释有关的技能。此项目在原位频率产生振动光谱/显微镜（SFG）中使用以探测被吸附到电极上的分子，而第二谐波产生显微镜（SHG）有助于确定电极的电子状态和对称性的电子状态。由于SHG各向异性与表面晶体学有关，因此这些技术的组合导致表面化学和潜在晶体学的相关图的产生。然后，在反应条件下，使用循环伏安法和亚微米分辨率询问表面反应性。这样，评估了多晶表面中相邻晶粒的影响。这项工作的更广泛的影响有可能提高表面敏感的光谱和显微镜工具，这些工具可以提高对电极如何影响异质电催化的化学和物理理解。该奖项反映了NSF的法定任务，并认为通过基金会的知识智能和更广泛的影响审查Criteria，它被视为值得通过评估的支持。