Professor Caroline Saouma
Professor Caroline Saouma
Department of Chemistry
University of Utah
Host: Professor Connie Lu
Thermodynamic and mechanistic studies of CO2 reduction catalysts
The increase in global energy demands, coupled with growing environmental concerns, necessitates the development of viable technologies to store solar energy. Towards this end, my group is focused on developing efficient catalysts that convert CO2 to CO, methanol or formic acid. My talk will first describe our mechanistic studies on known CO2 hydrogenation catalysts, whereby mechanistic insight is gleaned through thermochemical studies, and allows for tuning the product selectivity. We also have uncovered a unique mechanism for CO2 hydrogenation, whereby CO2 must first bind to the ligand before subsequent reduction occurs. I will then discuss how we have used the same thermochemical approach to study the mechanism of electrocatalytic CO2 reduction in a combined carbon capture & reduction system. Finally, I will present a novel ligand scaffold that, when put on Co, allows for both the hydrogenation of CO2 to formate and the electrochemical reduction of CO2 to formate; this is unique in that no H2 is produced electrocatalytically. The collective work underscores the importance of the effective hydricity as a parameter of interest and in using thermochemical parameters to rationalize and uncover alternative mechanisms. The studies presented are contextualized in developing an understanding of how to rationally design energy-efficient CO2 reduction catalysts.
Caroline Saouma was born in Pittsburgh, PA, and grew up between Boulder, CO, and Lausanne, Switzerland. After visiting National Institute of Standards and Technology as a second grader, she was hooked on science. She went to the Massachusetts Institute of Technology to complete her bachelor’s degree (chemistry, 2005), where she did research with Steve Lippard on developing cisplatin analogues that target specific malignancies. She then went to Caltech to complete her doctorate under the supervision of Jonas Peters, where she investigated iron-mediated reductions of CO2 and N2. Her postdoctoral work with Jim Mayer focused on Proton-Coupled Electron Transfer (PCET) reactions of synthetic FeS clusters and MOFs. She joined the faculty at the University of Utah as an assistant professor in 2014, where her research is focused on mechanistic studies and catalyst design for CO2 reduction. She is the recipient of the National Science Foundation CAREER (2020) and is a Chemical Communications Emerging Investigator (2020). Outside of chemistry, she is an avid athlete; as a graduate student she was training to row with the US national team, and she now enjoys cross country skiing and road biking.
Professor Saouma's research program is focused on developing a fundamental understanding of transition-metal mediated small molecule activation, as it pertains to energy conversion and green synthetic applications. Using motifs found in Nature, researchers in her lab design and develop transition metal complexes that will allow them to test ideas on how to selectively achieve complex multi-e–/multi-H+ chemical transformations at low over-potentials. Topics of current interest include (i) activation of O2 for fuel cell and synthetic applications, and (ii) electrocatalytic CO2 fixation and CO2 reduction to methanol. Detailed reactivity and mechanistic studies will be combined with a wealth of data from spectroscopic and structural techniques to provide insights to these transformations, which will allow for the rational design of functional catalysts.