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

鉴于全球努力通过向更清洁的能源过渡来应对气候变化，电化学领域在实现可再生能源方面变得至关重要。清洁电能可用于驱动各种化学反应，例如将二氧化碳转化为有价值的产品和生产氢气。这些反应的效率很大程度上取决于电催化剂，电催化剂是使这些反应有效发生的材料。传统上，这些电催化剂已经使用常规的电化学方法进行了测试。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测量，这掩盖了各个催化剂之间的差异。2)他们提供了有限的洞察机制和活动发生在复杂的电催化剂界面。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。参与该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，大大提高他们的技术技能。此外，Sundaresan实验室计划通过暑期研究项目和外展活动吸引密西西比少数民族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研究员项目将为密西西比大学（UM）的助理教授提供奖学金，并为研究生提供培训。纳米粒子电催化剂在尺寸、形状和表面化学方面表现出异质性，导致它们之间的反应性差异。传统的电化学测量反映了非均相系统的平均行为，而不能解释个体差异。该项目的总体目标是开发和采用高分辨率扫描探针电化学显微镜-扫描电化学电池显微镜（SECCM）-结合新颖的光学方法，用于在单一实体水平上高通量筛选电催化剂。这将在德克萨斯州A M大学的Lane Baker教授的指导下完成，该大学是扫描探针技术的世界领导者。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单个电催化剂阵列的电活性，以及2）验证电荧光探针用作测量电化学活性的代理。这两种策略使得电催化剂的高通量和大规模并行筛选成为可能。此外，这种方法提供了洞察每个实体如何独特地有助于在传统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UM的研究和分析化学课程培训研究生和本科生，以及电化学学会（ECS）为代表性不足的学生开展的外展活动该奖项反映了NSF的法定使命，并被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准。

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.