RII Track-4:NSF: Integrated Electrochemical-Optical Microscopy for High Throughput Screening of Electrocatalysts

鉴于全球通过过渡到更清洁的能源来应对气候变化的努力，电化学领域已成为使可再生能源变得实用的关键。清洁电能可用于推动各种化学反应，如将二氧化碳转化为有价值的产品和生产氢气。这些反应的效率在很大程度上取决于电催化剂，电催化剂是使这些反应能够高效发生的材料。传统上，这些电催化剂是用传统的电化学方法进行测试的。然而，这些方法有两个关键的局限性，1)它们提供了电催化剂效率的平均衡量标准，掩盖了不同催化剂之间的差异。2)它们对发生在复杂电催化剂界面上的机理和活性提供了有限的见解。该项目旨在通过开发一种相关的电化学-光学显微镜来解决这些限制，该显微镜能够以高通量的方式单独测试电催化剂。参与这个项目的学生将在新的测量和表征技术以及尖端的纳米制造方法方面获得宝贵的经验，显著提高他们的技术技能。此外，Sundaresan实验室计划通过暑期研究计划和外展活动吸引密西西比州少数族裔服务机构的本科生和K-12学生，以鼓励学生攻读STEM学位。RII Track-4 EPSCoR研究人员项目将为密西西比大学(UM)的一名助理教授提供奖学金，并为一名研究生提供培训。纳米粒子电催化剂在大小、形状和表面化学上表现出异质性，导致它们之间的反应活性不同。传统的电化学测量反映了多相体系的平均行为，不考虑个体差异。该项目的总体目标是开发和使用高分辨率扫描探针电化学显微镜-扫描电化学细胞显微镜(SECCM)-与新的光学方法相结合，在单一实体水平上高通量筛选电催化剂。这将在德克萨斯农工大学的莱恩·贝克教授的指导下完成，他是扫描探头技术的世界领先者。相关的SECCM光学技术将：1)以直接方法而不是光栅扫描方法探测具有明确定义的颗粒到颗粒距离的一组单独的电催化剂的电活性，以及2)验证电致荧光探针作为测量电化学活性的代理使用。这两种策略使得高通量和大规模并行筛选电催化剂成为可能。此外，这种方法提供了洞察每个实体如何独特地贡献在传统的电化学测量中看到的整体响应。更广泛的影响包括密西西比州的一种新的测量技术，可用于通过密歇根大学的研究和分析化学课程培训研究生和本科生，以及在密歇根大学电化学学会(ECS)分会为代表不足的学生开展的外联活动。该奖项反映了NSF的法定使命，并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，被认为值得支持。

In light of the global effort to combat climate change by transitioning to cleaner energy sources, the field of electrochemistry has become essential in making renewable energy practical. Clean electrical energy can be used to drive various chemical reactions, such as converting carbon dioxide into valuable products and producing hydrogen. The efficiency of these reactions largely depends on electrocatalysts, which are materials that enable these reactions to occur efficiently. Traditionally, these electrocatalysts have been tested using conventional electrochemical methods. However, these methods have two key limitations, 1) They provide an average measure of electrocatalyst efficiency, which masks the differences among individual catalysts. 2) They offer limited insights into the mechanisms and activity happening at the complex electrocatalyst interface. This project aims to address these limitations by developing a correlated electrochemical-optical microscope capable of testing electrocatalysts individually and in a high-throughput manner. Students involved in this project will gain valuable experience in new measurement and characterization techniques, as well as cutting-edge nanofabrication methods, significantly enhancing their technical skills. Furthermore, the Sundaresan Laboratory plans to engage undergraduate and K-12 students from minority-serving institutions in Mississippi through summer research programs and outreach activities to encourage students to pursue STEM degrees.The RII Track-4 EPSCoR Research Fellows project would provide a fellowship to an Assistant Professor and offer training to a graduate student at the University of Mississippi (UM). Nanoparticle electrocatalysts exhibit heterogeneity in size, shape, and surface chemistry, leading to differences in reactivity among them. Traditional electrochemical measurements reflect the average behavior of a heterogeneous system and do not account for individual variations. The overarching goal of this project is to develop and employ high-resolution scanning probe electrochemical microscopy - scanning electrochemical cell microscopy (SECCM) - coupled with novel optical methods for high-throughput screening of electrocatalysts at a single-entity level. This will be accomplished under the mentorship of Prof. Lane Baker, Texas A&M University, a world leader in scanning probe techniques. The correlated SECCM-optical technique will: 1) probe the electroactivity of an array of individual electrocatalysts with a well-defined particle-to-particle distance in a direct approach rather than the raster scan approach, and 2) validate electrofluorogenic probes for use as a proxy for measuring electrochemical activity. These two strategies enable high-throughput and massively parallel screening of electrocatalysts. Furthermore, this approach offers insights into how each entity uniquely contributes to the ensemble response seen in traditional electrochemical measurements. The broader impacts include a new measurement technique for the state of Mississippi, available for training graduate and undergraduate students through research and analytical chemistry courses at UM, as well as outreach activities for underrepresented students with the Electrochemical Society (ECS) chapter at UM.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.