CAS: Design and Mechanistic Understanding of Selective Electrocatalysts Based on Earth-Abundant Metal Compounds

University Of Wisconsin-Madison, Madison WI

Investigators

Abstract

With this award,the Chemical Catalysis Program of the Division of Chemistry is supporting Drs. Song Jin and Jordan Schmidt of the University of Wisconsin-Madison to combine theory and experiment to design, develop, and understand new electrochemical methods to generated hydrogen peroxide (H2O2) from molecular oxygen. Hydrogen peroxide (H2O2) is an environmentally benign oxidant with many industrial and environmental applications. It is also a recommended disinfectant in general, including for the novel coronavirus responsible for the COVID-19 pandemic. The current commercial production of H2O2 is characterized by significant cost, energy consumption, and safety concerns. To be economically competitive the current process is practiced in a few large, centralized manufacturing plants. In comparison, small scale, decentralized, on-site production of H2O2 directly from oxygen using electricity could be a more effective and sustainable approach. However, electrochemical approaches to H2O2 need to be much more efficient and less costly to be viable. The success of this project can facilitate the efficient decentralized production of H2O2 and have broad technological impacts related to the environment, sustainability, and the healthcare fiels. This project includes a significant educational outreach component and seeks to build a more diverse scientific workforce through inclusive training. Drs. Song Jin and Jordan Schmidt and their team combine theory and experiment to exploit the unique attributes of unexplored metal compound electrocatalysts to design, develop, and understand new and selective electrocatalysts based on metal chalcogenides for the selective two-electron oxygen reduction reaction (2e ORR) in acidic and neutral solutions. Such selective 2e ORR electrocatalysts can facilitate decentralized electrochemical production of H2O2, an environmentally benign oxidant with diverse applications in industrial, environmental, and healthcare settings. Density functional theory calculations and kinetic models provide detailed insights into activity and selectivity and identify promising candidate structures among transition metal chalcogenides for subsequent synthesis and performance evaluation. Electrochemical and (in situ) spectroscopic studies reveal catalyst activity, selectivity, and potential-dependent reaction intermediates, with computational examination providing mechanistic insights into the catalytic mechanism(s) and further design principles governing catalyst selectivity and stability. Understanding and rationally designing complex metal compound catalysts for enabling various selective electrocatalytic reactions can lead to fundamental and transferrable insights into how complex structural motifs influence catalyst activity and selectivity. The success of this project can also facilitate the efficient decentralized electrochemical production of H2O2 and, as such, has the potential for broad scientific and societal impact. 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.