Dynamic Nuclear Polarization and its Applications in Heterogeneous Catalysis

Event
Friday, February 3, 2023 - 3:20pm
Event Type: 

headshot of speaker

Dr. Frederick Perras, Ames Laboratory

Host: Dr. Rossini

Solid-state NMR can theoretically reveal the most detailed structural insights for non-crystalline materials, in principle going as far as revealing full three-dimensional models of the structure. This potential, however, is most often hampered by the technique’s low sensitivity, originating from the poor Boltzmann polarization of the NMR transitions. This presentation will introduce the dynamic nuclear polarization (DNP) technique, which couples EPR spectroscopy to NMR to yield dramatic enhancements in sensitivity, and how we can use theory to further improve DNP performance. One of the fields that has benefitted the most from DNP has been heterogeneous catalysis. Dilute sites distributed on the surfaces of materials can be readily probed using DNP-enhanced NMR, enabling for the use of NMR-based interatomic distance measurements that reveal the 3D conformations of surface sites in addition to their dynamics.

Frédéric A. Perras is a Scientist III in the Chemical and Biological Sciences Division of Ames National Laboratory. Originally from Ottawa, ON, Canada, he completed his BSc (2010) and PhD (2015) in Chemistry at the University of Ottawa working with Prof. David. L. Bryce. He then moved to Ames National Laboratory to work with Prof. Marek Pruski as a Spedding, and later Banting, postdoctoral fellow. He was hired as an Ames National Laboratory Scientist II in 2019, and was promoted to Scientist III in 2022. Since 2021, he is the group leader for the Ames National Laboratory CBS Solid-State NMR research group. He is the recipient of the Raymond Andrew prize, the IUPAC-Solvay International Award for Young Chemists, and a DOE Early career award. His research focuses on the development of new solid-state NMR methods with an emphasis on their applications to understanding heterogeneous catalytic processes.