Learning From 'Systematic' Structural Variation in Porous Materials

Abstract:

The Notestein group studies catalytic transformations with the goal of improving the production of large-scale chemicals and fuels. Our preferred approach is through longitudinal studies of families of materials with tuned physical properties that might shed light on the underlying physical phenomena. This can be challenging because Arrhenius-type exponential dependances of rate on catalyst structure force most of the ‘interesting’ catalysts to have similar compositions. This talk will discuss a few recent examples from the group. In the first, we look at Zr-based metal organic frameworks (MOFs) as catalysts for H-shift catalysis (the MPV reaction). The pore structure of these MOFs tends to be the focus of most attention, but here we show that the local coordination geometry around the Zr-based active sites controls reaction rates and selectivities. In a second example, we will examine methane conversion in substituted zeolites. Mo-substituted zeolites have been the benchmark materials for the production of aromatics, but a systematic re-analysis of the literature indicates that there is little potential for new catalyst development around this composition. Conversely, somewhat accidental variation in the structure of Fe-substituted zeolites shows a strong structure-property correlation, suggesting avenues for future optimization. The talk will close out with reflections on how these types of materials-based studies might (or might not) find success in the highly-automated research future that many federal agencies envision.

Biography:

Justin Notestein is a professor of chemical and biological engineering. He received his BSE from Princeton in 2001, a PhD from Berkeley in 2006, and did a brief postdoc at Urbana-Champaign. His entire academic career has been at Northwestern University, where he has been a professor for 18 years and is currently Chair of the department and will begin as Associate Dean in September. He has advised over 50 PhD, thesis masters, and postdocs in chemical engineering, materials science, environmental engineering, and chemistry. He has authored over 150 articles and inventions in catalysis and frequently works with industrial partners. He is the current director of the Center for Catalysis and Surface Science, a multidisciplinary catalysis center at Northwestern with over 75 years of history. He has been recognized for excellence in education including the Mashiro and Eiko Meshii Award for design research and education.