Collaborative Research: A Mechanistic Study of Chemical Enhancement in Surface Enhanced Raman Spectroscopy and Graphene Enhanced Raman Spectroscopy

合作研究：表面增强拉曼光谱和石墨烯增强拉曼光谱化学增强的机理研究

• 批准号: 1708581
• 负责人: Stephen Cronin
• 金额: $ 26.52万
• 依托单位: University of Southern California
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-07-15 至 2021-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1708581&HistoricalAwards=false
• 关键词: Collaborative; Research; Mechanistic; Study; Chemical

With support from the Chemical Measurement and Imaging Program in the Division of Chemistry, Professor Cronin at University of Southern California and Professor Jensen at Pennsylvania State University investigate the use of Raman spectroscopy as a powerful tool that measures the energies of specific bond stretches. This technique provide the unique fingerprint for chemical identification. As such, Raman spectroscopy is extremely useful for a number of applications in chemical, environmental and threat detection monitoring. While a highly useful technique, the Raman scattering cross-section of most molecules is extremely small, and this generally limits its potential uses. Surface Enhanced Raman Scattering (SERS) and Graphene Enhanced Raman Scattering (GERS), the techniques investigated in this research project, can be used to improve the small signal intensities, thus making Raman spectroscopy-related applications more practical. In terms of broader impacts Dr. Cronin creates workshops for Los Angeles high school chemistry teachers. He leverages existing relationships between USC and its neighboring high schools (e.g., USC's Good Neighbors Campaign, Joint Education Project, and the Service Learning Program) to increase the attendance from disadvantaged schools (i.e., central Los Angeles inner city schools) serving underrepresented minority groups. The content of the workshop is reformulated to expose underrepresented students to the results and, more importantly, the excitement of research. Research projects for undergraduate students introduce them to fundamental scientific research and give them confidence to pursue careers in science and engineering. A new module devoted to SERS is developed for a new course at USC on nanoscience and nanotechnology, and their research accomplishments are discussed in class and integrated into the curriculum. Professor Jansen uses a website, nanoHub.org, to share their computational tools with scientists outside of his labs. In this collaboration, Professors Cronin and Jensen investigate the mechanism behind the strong spectroscopic responses observed in two surface-based spectroscopic techniques: Surface Enhanced Raman Scattering (SERS) and Graphene Enhanced Raman Scattering (GERS). They use both experimental and computational tools to carefully isolate the enhanced Raman signals caused by Chemical Enhancement (CE) from those signals caused by ElectroMagnetic Enhancement (EM) in order to understand the CE mechanism. Specifically, Professor Cronin's group at USC performs Raman spectroscopy of single molecules on various SERS substrates, which enables a direct comparison with the theoretical calculations preformed at the Jensen's group at PSU. The Raman spectra are collected under various electrochemical conditions in order to explore the role of the molecule-metal energy level alignment and decouple the vibrational-mode-specific chemical enhancement from the uniform chemical enhancement. Professor Jensen's first principles calculations provide a detailed theoretical framework for interpreting chemical enhancement in SERS and GERS spectra to facilitate a better understanding of the chemical enhancement mechanism. Students in both groups experience the interdisciplinary training opportunities. Both groups' are actively engaged in outreach activities to local high school teachers and general public.

在化学系化学测量和成像项目的支持下，南加州大学的克罗宁教授和宾夕法尼亚州立大学的詹森教授研究了拉曼光谱作为测量特定键拉伸能量的强大工具的用途。 该技术为化学鉴定提供了独特的指纹。因此，拉曼光谱对于化学、环境和威胁检测监测领域的许多应用非常有用。 虽然这是一种非常有用的技术，但大多数分子的拉曼散射截面非常小，这通常限制了其潜在用途。本研究项目研究的技术包括表面增强拉曼散射（SERS）和石墨烯增强拉曼散射（GERS），可用于提高小信号强度，从而使拉曼光谱相关应用更加实用。就更广泛的影响而言，克罗宁博士为洛杉矶高中化学教师举办了研讨会。他利用南加州大学与其邻近高中之间的现有关系（例如南加州大学的好邻居运动、联合教育项目和服务学习计划）来增加弱势学校（即洛杉矶市中心内城学校）的入学率，为代表性不足的少数群体提供服务。研讨会的内容经过重新设计，让代表性不足的学生了解结果，更重要的是，了解研究的兴奋点。本科生研究项目向他们介绍基础科学研究，并让他们有信心从事科学和工程职业。南加州大学纳米科学和纳米技术的新课程开发了一个专门针对 SERS 的新模块，他们的研究成果在课堂上进行讨论并融入到课程中。 詹森教授使用 nanoHub.org 网站与实验室外的科学家分享他们的计算工具。 在这次合作中，克罗宁教授和詹森教授研究了两种基于表面的光谱技术中观察到的强光谱响应背后的机制：表面增强拉曼散射（SERS）和石墨烯增强拉曼散射（GERS）。 他们使用实验和计算工具仔细地将化学增强 (CE) 引起的增强拉曼信号与电磁增强 (EM) 引起的信号分开，以便了解 CE 机制。 具体来说，南加州大学克罗宁教授的团队在各种 SERS 基底上对单分子进行拉曼光谱分析，这使得能够与 PSU 詹森团队进行的理论计算进行直接比较。 在各种电化学条件下收集拉曼光谱，以探索分子-金属能级排列的作用，并将振动模式特异性化学增强与均匀化学增强解耦。 Jensen教授的第一原理计算为解释SERS和GERS光谱中的化学增强提供了详细的理论框架，以促进更好地理解化学增强机制。两组学生都体验到跨学科培训的机会。 两个团体都积极参与当地高中教师和公众的外展活动。

项目成果

Monitoring Local Electric Fields using Stark Shifts on Napthyl Nitrile-Functionalized Silicon Photoelectrodes

使用萘基腈官能化硅光电极上的斯塔克位移监测局部电场

• DOI: 10.1021/acs.jpcc.0c03966
• 发表时间: 2020-07-10
• 期刊: Journal of Physical Chemistry C
• 影响因子: 3.7
• 作者: Haotian Shi;Ryan T. Pekarek;Ran Chen;Boxin Zhang;Y. Wang;Indu Aravind;Zhi Cai;L. Jensen;N. Neale;S. Cronin
• 通讯作者: S. Cronin

Stacking Independence and Resonant Interlayer Excitation of Monolayer WSe 2 /MoSe 2 Heterostructures for Photocatalytic Energy Conversion

用于光催化能量转换的单层WSe 2 /MoSe 2 异质结构的堆叠独立性和共振层间激发

• DOI: 10.1021/acsanm.9b01898
• 发表时间: 2020-01
• 期刊: ACS Applied Nano Materials
• 影响因子: 5.9
• 作者: Chen, Jihan;Bailey, Connor S.;Cui, Dingzhou;Wang, Yu;Wang, Bo;Shi, Haotian;Cai, Zhi;Pop, Eric;Zhou, Chongwu;Cronin, Stephen B.
• 通讯作者: Cronin, Stephen B.

Nanoparticle-Enhanced Plasma Discharge Using Nanosecond High-Voltage Pulses

使用纳秒高压脉冲的纳米粒子增强等离子体放电

• DOI: 10.1021/acs.jpcc.9b12054
• 发表时间: 2020-04
• 期刊: The Journal of Physical Chemistry C
• 作者: Zhao, Bofan;Aravind, Indu;Yang, Sisi;Cai, Zhi;Wang, Yu;Li, Ruoxi;Subramanian, Sriram;Ford, Patrick;Singleton, Daniel R.;Gundersen, Martin A.;et al
• 通讯作者: et al

Monitoring Reaction Intermediates in Plasma-Driven SO 2 , NO, and NO 2 Remediation Chemistry Using In Situ SERS Spectroscopy

使用原位 SERS 光谱监测等离子体驱动的 SO 2 、NO 和 NO 2 修复化学中的反应中间体

• DOI: 10.1021/acs.analchem.0c05413
• 发表时间: 2021-04
• 期刊: Analytical Chemistry
• 影响因子: 7.4
• 作者: Li, Shujin;Zhao, Bofan;Aguirre, Alejo;Wang, Yu;Li, Ruoxi;Yang, Sisi;Aravind, Indu;Cai, Zhi;Chen, Ran;Jensen, Lasse;et al
• 通讯作者: et al

Plasmon-Resonant Enhancement of Photocatalysis on Monolayer WSe 2

单层 WSe 2 光催化的等离激元共振增强

• DOI: 10.1021/acsphotonics.9b00089
• 发表时间: 2019-02
• 期刊: ACS Photonics
• 影响因子: 7
• 作者: Chen, Jihan;Bailey, Connor S.;Hong, Yilun;Wang, Li;Cai, Zhi;Shen, Lang;Hou, Bingya;Wang, Yu;Shi, Haotian;Sambur, Justin;et al
• 通讯作者: et al