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

University Of Illinois At Urbana-Champaign, Urbana IL

Investigators

Abstract

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.