Heterogeneous Catalysts Tailored for Parahydrogen Induced Nuclear Spin Polarization

University Of Florida, Gainesville FL

Investigators

Abstract

With support from the Chemical Measurement and Imaging Program in the Division of Chemistry, Professors Bowers and Hagelin-Weaver and their groups at the University of Florida will combine state-of-the-art catalyst synthesis, characterization, and reaction studies to identify and mitigate the processes that reduce pairwise hydrogenation during Parahydrogen Induced Polarization (PHIP). PHIP is a robust and inexpensive method used for sensitivity enhanced nuclear magnetic resonance (NMR) spectroscopy and magnetic resonance imaging. In addition to potential biomedical utilization, PHIP is a powerful method for the study of hydrogenation catalysis and new insights gained during this proposed research may well have a major impact on the field of catalytic reactions, beyond hydrogenation. Students will receive interdisciplinary training in catalysis, reactor design, materials characterization, and surface chemistry. The PIs also propose to reach out to teachers from rural and urban schools serving 50% or more students from socio-economically underserved homes by coordinating with UF's CPET programs for teacher recruitment. The proposed outreach efforts will provide an innovative and productive linkage between cutting-edge research and secondary school STEM education. The proposed research seeks to identify correlations between catalyst properties, activity and pairwise selectivity. The proposed research plan will be the first to combine state-of-the art nanoparticle fabrication strategies with precision atomic layer deposition (ALD). Interpretation of PHIP data will be guided by spin density matrix theory. Development of unique PHIP NMR instrumentation is another key element of the project. Pairwise selectivities obtained with oxides and oxide supported metal particles are currently limited to a few percent. Attaining substantially higher pairwise selectivity using engineered oxide-supported metal nanoparticle catalysts would be a transformative outcome of the project. This low pairwise selectivity problem will be addressed through fundamental kinetic and mechanistic studies. The proposed studies also aim to broaden the variety of targets that can be hyperpolarized by this class of catalyst.