CAREER: SuSChEM: Experimental characterization of catalytic water oxidation reaction intermediates

University Of Wisconsin-Madison, Madison WI

Investigators

Abstract

With this CAREER Award, the Chemical Structure, Dynamics & Mechanisms B program is supporting the research of Professor Etienne Garand of the University of Wisconsin-Madison. Professor Garand will use cryogenic ion infrared predissociation spectroscopy to characterize reaction complexes present in catalytic water oxidation reactions. First, a methodology will be developed to isolate catalytic reaction complexes generated under realistic electrochemical conditions as well as by controlled gas-phase reactions. The structures of these isolated complexes will then be characterized in detail using a method based on a unique combination of mass spectrometry and vibrational predissociation spectroscopy. Subsequent studies involving systematic variations of the catalyst structure will reveal the influence of ligand environment and metal center on the nature and electronic structure of the reaction complexes. The active control of the solvent network in promoting processes such as proton coupled electron transfer will also be probed in detail. The methodology developed here will allow for precise and systematic spectroscopic characterization of reactive species, providing a detailed description of the molecular level interactions involved in the water oxidation process and elucidating their relationship with the catalyst structure. Lastly, the results from these studies will also provide stringent benchmarks for theoretical methods used to understand the mechanisms of such molecular catalysts. The project will improve our understanding of the mechanism of catalytic water oxidation reactions, which will help the development of more efficient water oxidation catalysts. Water oxidation reactions play a significant role in the conversion of solar energy into chemical energy. Professor Garand will also initiate educational projects that interweave research and teaching. To demystify mass spectrometry for the general audiences, Professor Garand will develop demonstrations based on a mechanically rotating saddle analog of the Paul trap and a mass-selective quadrupole trap for macroscopic particles. These interactive apparati will illustrate basic concepts in mass spectrometry such as ion trapping, mass selection and collision activation. They will be integrated into a general chemistry class and distributed more broadly through online videos. Such visual and hands-on demonstrations of the concepts of mass spectrometry will have the potential to engage the interest of the general public and undergraduate students, providing them with a deeper understanding and appreciation for the sciences behind these widely used instruments. Professor Garand will also provide initiation to research for undergraduate students through integrated research in classes and summer internships. Such experiences can provide the students with a well-rounded educational experience as they decide their future paths.