Collaborative Research: Detailed Mechanistic Pathways of Surface Catalysis using SERS Spectroscopy: A Joint Theoretical and Experimental Synergistic Approach

合作研究：使用 SERS 光谱的表面催化的详细机理路径：理论和实验联合协同方法

• 批准号: 2106480
• 负责人: Stephen Cronin
• 金额: $ 26.46万
• 依托单位: University of Southern California
• 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=2106480&HistoricalAwards=false
• 关键词: Collaborative; Research; Detailed; Mechanistic; Pathways

With support from the Chemical Measurement and Imaging (CMI) Program in the Division of Chemistry, Professors Stephen Cronin at the University of Southern California (USC) and Lasse Jensen at Pennsylvania State University (PSU) will investigate the physical mechanisms underlying a measurement technique called surface-enhanced Raman scattering (SERS). This work closes the loop between theory and experiment, providing a detailed quantum mechanical picture of the molecules adsorbed on metal surfaces during catalytic reactions. The project uses a general SERS-based approach to study reaction mechanisms associated with surface catalysis, and also toward the goal of imaging chemical reactivity of catalytic surfaces with sub-micron spatial resolution. The information provided by experimental SERS spectra is somewhat limited without the aid of supporting theoretical work to provide atomistic insight on the underlying processes. Therefore, it is crucial to carry out theoretical calculations in parallel with the experiments in order to obtain a detailed picture of the molecules and their reactions on surfaces, including the charge transfer between a molecule and the metal surface, to distinguish between physisorption and adsorption, to establish key catalytically active sites, and to identify surface-bound intermediate species and the relative importance of other key aspects of catalytic reactions. In this collaborative project, the experimental research group led by Professor Stephen Cronin (USC) will record the SERS spectra of electrode surfaces under electrochemical working conditions using a water immersion lens, and the theoretical research group led by Professor Lasse Jensen (PSU) will use time-dependent density functional theory (TD-DFT) and related methods to simulate adsorbed chemical species on metal surfaces. The direct correspondence between the theoretical calculations and experimental measurements in this effort promises to provide a robust test of the basic hypotheses underlying charge flow between the adsorbate and metal surface. The team is testing their hypothesis that dynamic charge flow between a molecule and the metal surface plays an important role in the SERS enhancement process and can be used to extract important chemical information from the mode-dependent SERS enhancement factors. The researchers are testing this hypothesis by correlating product formation with in situ SERS spectra that they record under electrochemical working conditions. They will also examine a hypothesis that the SERS enhancement is either correlated or anti-correlated with catalytic activity. This hypothesis stems from the idea that both the enhancement and the catalytic activity depend on the degree to which a given reactant or intermediate is bound to the metal surface, which is ultimately based on the amount of charge transfer that occurs at the interface. Additionally, the team plans to use the relative SERS enhancement of different vibrational modes to image reactivity and/or reactive sites based on the information they learn about the relationship between dynamic charge flow and SERS activity.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.

在化学系化学测量和成像 (CMI) 项目的支持下，南加州大学 (USC) 的 Stephen Cronin 教授和宾夕法尼亚州立大学 (PSU) 的 Lasse Jensen 教授将研究称为“测量技术”的测量技术背后的物理机制。表面增强拉曼散射（SERS）。这项工作闭合了理论和实验之间的循环，提供了催化反应过程中吸附在金属表面的分子的详细量子力学图像。该项目使用基于 SERS 的通用方法来研究与表面催化相关的反应机制，并实现以亚微米空间分辨率对催化表面的化学反应性进行成像的目标。如果没有支持理论工作来提供对底层过程的原子洞察，实验 SERS 光谱提供的信息在某种程度上是有限的。因此，与实验并行进行理论计算至关重要，以获得分子及其在表面反应的详细图像，包括分子与金属表面之间的电荷转移，以区分物理吸附和吸附，建立关键的催化活性位点，并确定表面结合的中间体物种以及催化反应其他关键方面的相对重要性。在这个合作项目中，Stephen Cronin教授（USC）领导的实验研究小组将使用水浸透镜记录电化学工作条件下电极表面的SERS光谱，Lasse Jensen教授领导的理论研究小组（PSU）将使用瞬态密度泛函理论 (TD-DFT) 和相关方法来模拟金属表面吸附的化学物质。这项工作中理论计算和实验测量之间的直接对应有望为吸附物和金属表面之间的电荷流的基本假设提供可靠的测试。该团队正在测试他们的假设，即分子和金属表面之间的动态电荷流在 SERS 增强过程中起着重要作用，并且可用于从模式相关的 SERS 增强因子中提取重要的化学信息。研究人员正在通过将产物形成与他们在电化学工作条件下记录的原位 SERS 光谱相关联来测试这一假设。他们还将检验 SERS 增强与催化活性相关或反相关的假设。这一假设源于这样的想法：增强活性和催化活性都取决于给定反应物或中间体与金属表面结合的程度，这最终取决于界面处发生的电荷转移量。此外，该团队计划根据他们了解到的动态电荷流和 SERS 活动之间关系的信息，使用不同振动模式的相对 SERS 增强来对反应性和/或反应位点进行成像。该奖项反映了 NSF 的法定使命，并被视为值得通过使用基金会的智力优点和更广泛的影响审查标准进行评估来支持。

项目成果

Dynamic Study of Intercalation/Deintercalation of Ionic Liquids in Multilayer Graphene Using an Alternating Current Raman Spectroscopy Technique

使用交流拉曼光谱技术动态研究多层石墨烯中离子液体的嵌入/脱嵌

• DOI: 10.1021/acs.jpclett.3c01686
• 发表时间: 2023-08
• 期刊: The Journal of Physical Chemistry Letters
• 作者: Cai, Zhi;Weinstein, Haley;Aravind, Indu;Li, Ruoxi;Weng, Sizhe;Zhang, Boxin;Habif, Jonathan L.;Cronin, Stephen B.
• 通讯作者: Cronin, Stephen B.

SERS Detection of Charge Transfer at Electrochemical Interfaces Using Surface-Bound Ferrocene

使用表面结合二茂铁检测电化学界面的电荷转移的 SERS

• DOI: 10.1021/acs.jpcc.3c01973
• 发表时间: 2023-07
• 期刊: The Journal of Physical Chemistry C
• 作者: Li, Ruoxi;Chaudhry, Imran;Tseng, Cindy;Weng, Sizhe;Wang, Yu;Zhao, Bofan;Aravind, Indu;Cai, Zhi;Dawlaty, Jahan;Jensen, Lasse;et al
• 通讯作者: et al