CAREER: Time-Resolved Studies of Charge Transfer and Chemical Reactivity at Photoelectrode-Electrolyte Interfaces

在这个由化学系化学结构动力学和机理（CSDM-A）项目支持的项目中，Yi Rao博士和他在犹他州州立大学（USU）的学生将开发复杂的激光技术，以探索在光电极-电解质界面将二氧化碳（CO2）转化为燃料。界面是薄的区域-几个分子宽-两个体相，如固体和液体，满足。在这种情况下，边界是在固体光电极、可以发生光激活反应的表面和可以导电的液体之间。这项研究正在推进我们对CO2在太阳能和电力驱动下的界面反应的认识。这项工作将整合科学培训和发现，使用基于激光的光谱工具作为其基石，以加强本科和研究生水平的教学。饶博士计划在教育背景下利用这一研究专长，为K-12学生举办光子燃料研讨会，并在当地社区举办USU Science Unwrapped外展活动。该项目的重点是使用新开发的界面选择性光谱工具，包括时间分辨电子和频产生（TR-ESFG）和时间分辨振动和频产生（TR-VSFG）在光电极-电解质界面的超快界面电荷转移和化学反应性。这些技术，最近开发和建立在饶组，提供了一个独特的机会，推进的PEC减少CO2和其他相关的界面现象的基础知识。在光电极-电解质界面处的光电化学反应的预期结果包括（1）界面状态的识别以及pH、离子种类、离子强度和施加电势的影响，（2）反应物和中间体的结合几何形状和强度的定量，以及（3）界面状态和中间体之间的关系的发展。这项工作的更广泛的社会影响是增加了对太阳能燃料界面化学反应性的理解。该项目还将使学生获得尖端激光技术、电化学和材料科学方面的宝贵经验。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

In this project supported by the Chemical Structure Dynamics and Mechanisms (CSDM-A) program of the Chemistry Division, Dr. Yi Rao and his students at Utah State University (USU) will develop sophisticated laser techniques to explore conversion of carbon dioxide (CO2) into fuels at photoelectrode-electrolyte interfaces. Interfaces are thin regions-a few molecules wide-where two bulk phases, such as a solid and liquid, meet. In this case, the boundary is between a solid photoelectrode, a surface where a light-activated reaction can occur, and a liquid that can conduct electricity. The research is advancing our knowledge of reactions of CO2 at interfaces, driven by solar energy and electricity. The work will integrate scientific training and discovery, using laser-based spectroscopic tools as its cornerstone to enhance teaching at the undergraduate and graduate levels. Leveraging this research expertise in an educational context, Dr. Rao plans to facilitate PHOTON FUELS workshops for K-12 students and hosts USU Science Unwrapped outreach events in the local community. This project focuses on ultrafast interfacial charge transfer and chemical reactivity at the photoelectrode-electrolyte interfaces using newly developed interface-selective spectroscopic tools, including time-resolved electronic sum frequency generation (TR-ESFG) and time-resolved vibrational sum frequency generation (TR-VSFG). These techniques, recently developed and established in the Rao group, provide a unique opportunity to advance fundamental knowledge of the PEC reduction of CO2 and other related interfacial phenomena. The expected outcomes of photoelectrochemical reactions at the photoelectrode-electrolyte interfaces include (1) identification of interfacial states and the effect of pH, ionic species, ionic strength, and applied potentials, (2) quantification of binding geometry and strengths of reactants and intermediates, and (3) development of a relationship between interfacial states and intermediates. A broader societal impact of this work is increased understanding of interfacial chemical reactivity of solar fuels. The project also will allow students to gain valuable experience in cutting-edge laser technology, electrochemistry, and materials science.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.