Scanning Electrochemical Microscopy of Single-Crystal Hydrogen Electrocatalysis

在化学系化学测量和成像计划的支持下，匹兹堡大学的Shigeru Ameiya教授和他的团队正在开发新的电化学方法，允许识别氢电催化的活性中间体和可能的反应路径。该项目的重点是深入了解氢电催化，这对于高效生产和利用可持续清洁的氢燃料以及电化学科学和技术的许多重要领域都是至关重要的。迫切需要对氢电催化的分子机理进行可靠的鉴定，这不仅是为了了解铂族金属的优异电催化活性，也是为了设计基于廉价和富含稀土元素的替代优良电催化剂。来自代表性不足群体的学生将经历跨学科培训，参与为拟议研究开发先进的电化学仪器，并在本科实验室实施复杂的电催化计算模拟。本项目专注于氢释放和氧化反应的定量研究，以解决这些两步两电子反应的混合路径。Ameiya实验室正在开发的新的纳米电化学方法将为测量氢原子的吸附能以及建立表面中间体的电化学特性提供机会。具体地说，Ameiya教授和他的研究小组正在开发和应用基于扫描电化学显微镜的瞬时纳米间隙伏安法，以分别确定每个电子转移和吸附步骤的热力学和动力学参数。使用表面原子排列良好的清洁单晶金属可以获得可靠的反应参数。根据实验确定的弱吸附和强吸附金属的每个反应的参数，将建立一个火山图，并将作为改进电催化剂的合理设计的有价值的指导。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

With support from the Chemical Measurement and Imaging Program in the Division of Chemistry, Professor Shigeru Amemiya and his group at the University of Pittsburgh are developing new electrochemical methods that allow for the identification of reactive intermediates and likely reaction pathways for hydrogen electrocatalysis. This project focuses on gaining an advanced understanding of hydrogen electrocatalysis, which is crucial for the efficient production and utilization of sustainable and clean hydrogen fuel and also for many important fields of electrochemical science and technology. Reliable identification of the molecular mechanism of hydrogen electrocatalysis is urgently demanded not only to understand the superior electrocatalytic activity of platinum-group metals but also to design alternative superior electrocatalysts based on inexpensive and earth abundant elements. Students from underrepresented groups will experience interdisciplinary training by participating in the development of advanced electrochemical instruments for the proposed research and in the implementation of the sophisticated computational simulation of electrocatalysis for an undergraduate laboratory.This project is focused on the quantitative study of both hydrogen evolution and oxidation reactions for the resolution of the intermingled pathways of these two-step two-electron reactions. New nanoelectrochemical methods being developed in the Amemiya laboratory will provide an opportunity to measure the adsorption energy of hydrogen atoms as well as establish the electrochemical identity of surface intermediates. Specifically, Professor Amemiya and his research group are developing and applying transient nanogap voltammetry based on scanning electrochemical microscopy to separately determine the thermodynamic and kinetic parameters of each electron transfer and adsorption step. Reliable reaction parameters can be obtained by employing clean single crystal metals with a well defined arrangement of surface atoms. A volcano plot will be established from the experimentally determined parameters of each involved reaction at both weakly and strongly adsorbing metals and will serve as a valuable guide for the rational design of improved electrocatalysts.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.