Scanning Electrochemical Microscopy of Single-Crystal Hydrogen Electrocatalysis

在化学系化学测量和成像项目的支持下，匹兹堡大学Shigeru Amemiya教授和他的团队正在开发新的电化学方法，可以识别反应中间体和氢电催化的可能反应途径。该项目的重点是深入了解氢电催化，这对于可持续清洁氢燃料的高效生产和利用以及电化学科学和技术的许多重要领域至关重要。对氢电催化的分子机理进行可靠的鉴定是迫切需要的，这不仅是为了了解铂族金属优越的电催化活性，也是为了设计基于廉价和富土元素的替代性优越电催化剂。来自未被充分代表的群体的学生将通过参与为拟议的研究开发先进的电化学仪器和在本科实验室实施复杂的电催化计算模拟来体验跨学科的训练。本项目主要对析氢和氧化反应进行定量研究，以确定这两步双电子反应的混合路径。Amemiya实验室正在开发的新型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。具体来说，Amemiya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态纳米间隙伏安法，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。通过使用表面原子排列明确的干净单晶金属，可以获得可靠的反应参数。根据实验确定的各反应在弱和强吸附金属时的参数，建立火山图，为合理设计改进的电催化剂提供有价值的指导。该奖项反映了美国国家科学基金会的法定使命，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。

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.