NSF-DFG EChem: Surface Stability and Oxygen Defect Chemistry of Pyrochlore and Related High-Performing Electrocatalysts for Oxygen Evolution Reaction

当氢被用作运输和固定电力应用的燃料时，水是唯一的主要副产品。因此，氢作为一种小分子燃料，可以在我国和全球向碳中和、可持续社会的能源转型中发挥重要作用。氢也是一种用于生产一系列产品的商品化学品，例如氨，它被用作食品生产和其他应用的肥料。目前，通过电力分解水分子来生产氢是一种能源密集型的方法，而且成本效益不高。为了减少生产氢气的能源负担，需要重大的技术进步。本提案的目标是通过了解水分解反应发生的详细原理以及如何设计用于生成绿色氢的电极材料来解决技术挑战。为了实现这一目标，该团队将研究设备中使用的催化剂材料如何在制氢条件下工作，以及电极材料内部发生了哪些结构变化。这些结果将有助于创造新的材料，提高氢气生产效率，使用更少的电力和规模。该项目还将通过伊利诺伊州学者本科研究和其他项目培养具有不同背景的学生，以提高他们在STEM领域的保留率，并确保他们拥有技术专长，成为未来高技能劳动力的一部分。低温聚合物电解质膜（PEM）电解槽直接水裂解制氢需要开发无贵金属、稳定、活性的电催化剂。有几个关键的挑战，其核心问题在于缺乏对表面原子和电子结构及其对电催化的影响的理解，特别是在反应条件下。来自伊利诺伊大学厄巴纳-香槟分校和德国达姆施塔特工业大学的跨学科团队将解决这一关键问题。该项目包括以下三个重点领域：1)研究焦氯化物氧化物OER电催化剂的结构-性能关系；2)在实际反应条件下利用x射线光电子能谱（XPS）研究原位电催化剂的新框架；3)研究缺陷化学及其对电催化性能的影响。该项目将揭示新的结构-属性关系；揭示制造稳定、活性OER电催化剂的新设计原则；在多学科环境中培养有能力的学生，使他们具备全球拓展的技能。该项目是通过“NSF-DFG在电合成和电催化领域的领导机构活动（NSF-DFG EChem）”的机会获得的，这是一项由国家科学基金会和德国研究机构（DFG）参与的合作征集。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。

When hydrogen is used as fuel for transportation and stationary power applications, water is the only major byproduct. Thus, hydrogen as a small molecule fuel can play an important role in our nation’s and global energy transitions to carbon-neutral, sustainable societies. Hydrogen is also a commodity chemical to make a range of products, such as ammonia, which is used as fertilizer for food production and other applications. Currently, production of hydrogen through splitting water molecules using electricity is energy intense and not cost effective. Major technological advancement is required to reduce the energy burden of producing hydrogen. The goal of this proposal is to address the technical challenges through understanding the detailed principles of how water-splitting reactions occur and how to design electrode materials for the generation of green hydrogen. To achieve this goal, the team will examine how the catalyst materials used in the device work under hydrogen production conditions and what structural changes occur within the electrode materials. These results will help to create new materials with enhanced efficiency for hydrogen production using less electricity and at scale. This project will also train students with diverse backgrounds through the Illinois Scholars Undergraduate Research and other programs to increase their retention in STEM fields and ensure they will have the technical expertise to be part of the highly skilled future workforce.Development of precious metal-free, stable, and active electrocatalysts is needed for electrochemical generation of hydrogen through direct water splitting by low-temperature polymer electrolyte membrane (PEM)-based electrolyzers. There are several key challenges, and at its core, the issue lies in the lack of understanding of surface atomic and electronic structures and their impacts on the electrocatalysis, especially under reactive conditions. The interdisciplinary team from the University of Illinois at Urbana-Champaign and Technical University of Darmstadt in Germany will tackle this critical issue. The project encompasses the following three focused areas: 1) examining the structure-property relationships of OER electrocatalysts made of pyrochlore oxides, 2) developing a new framework for studying in situ electrocatalysts using X-ray photoelectron spectroscopy (XPS) under realistic reaction conditions, and 3) studying the defect chemistry and its effect on electrocatalytic properties. The project will uncover new structure-property relationships; reveal new design principles for making stable, active OER electrocatalysts; and train able students in multidisciplinary environments with skills for global outreach.This project was awarded through the “NSF-DFG Lead Agency Activity in Electrosynthesis and Electrocatalysis (NSF-DFG EChem)" opportunity, a collaborative solicitation that involves the National Science Foundation and Deutsche Forschungsgemeinschaft (DFG).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.