March 8, 2021

Abstract — Multiple societally important chemical reactions rely on catalytic processing in aqueous conditions, including biomass processing, electrochemical energy conversion, fertilizer production, and water purification. A goal of our work is to learn the molecular-level ways in which solvent molecules influence catalysis, both so that we can better understand catalyst fundamentals and so that we can garner insight needed to design new catalysts and optimize catalytic operating conditions. Experiments and simulations have uncovered a variety of ways in which water solvent influences catalytic phenomena. For example, it alters reaction intermediate and transition state energies, co-catalyzes certain reaction steps, and controls which catalytic pathways are followed. However, a comprehensive picture about how H₂O molecules influence catalytic behavior, including their influence on catalytic energetics, remains unresolved. In this work, we use multiscale modeling involving density functional theory (DFT) and force-field molecular dynamics (ffMD) to examine how interfacial water influences the free energies of hydrophilic and hydrophobic adsorbates on hydrophobic Pt slabs, Pt electrodes, and supported Pt particles. We demonstrate how the polarities of the solvent, catalytic species, and catalyst interface influence catalytic enthalpies and entropies of solvation. Further, we show how solvents can be designed to control solvation thermodynamics in order to harness control over catalytic chemistry.

Biography — Rachel B. Getman is the Murdoch Family Endowed Associate Professor of Chemical and Biomolecular Engineering at Clemson University and the first woman to be tenured and promoted in her department in its 100-year history. Her research group uses quantum chemical calculations and Monte Carlo and molecular dynamics simulations to investigate molecular-level phenomena at fluid/solid interfaces. Dr. Getman is particularly interested in catalytic processes that occur under liquid solvent and in catalysis involving single transition metal cations. She holds a CAREER award from the National Science Foundation studying how the structure of liquid water influences the free energies of catalytic surface intermediates at water/metal catalyst interfaces, a Clemson University College of Engineering, Computing and Applied Sciences Dean’s Faculty Fellows Award, a Clemson University Board of Trustees Award for Excellence, and a Professor of Affordable Learning Award from the South Carolina Affordable Learning Group. Dr. Getman presently serves as a co-leader for the Multiscale Modeling and Computational Core Thrust of Materials Design and Assembly Excellence in South Carolina (MADE in SC), which is a $12 million initiative to promote the materials genome approach in the state of South Carolina. She also serves as the President of the Southeastern Catalysis Society and as a Member-At-Large for the CATL Division of the American Chemical Society. Dr. Getman earned dual BS degrees in Chemical Engineering and Business Administration from Michigan Technological University in 2004. She earned her PhD from the University of Notre Dame in 2009, where she worked with William Schneider simulating catalytic oxidations under ambient conditions. From 2009 – 2011, she was a Postdoctoral Research Fellow with Randall Snurr at Northwestern University, simulating gas storage in metal-organic frameworks (MOFs). She was a member of the Chicago Catalysis Club from 2005-2011 and won Best Poster at the 2008 Symposium. Dr. Getman started her independent career in August 2011. She presently lives in Upstate South Carolina with her husband and their two children, who are nine and seven years old. In her free time, Dr. Getman enjoys running exhaustively long distances and being a swim, soccer, softball, basketball, volleyball, cross country, and guitar parent.