Events

Many industrial chemical transformations are mediated by solid-state catalysts containing late-transitional metal nanostructures that serve as active sites. Efforts to optimize catalyst performance metrics (activity, selectivity, and stability) have led to the identification of bimetallic nanostructures that exhibit performance beyond what can be achieved by the constituent metals alone. Crucial for these optimization efforts is control of the physical and chemical interactions within bimetallic nanostructures. However, structure-function relationships often remain elusive in bimetallic catalysts at the active site scale due to the complex configurational space of structure structures that exists in this class of catalysts. Here, we will highlight 2 recent examples from my group where atomistic scale-structure function relationships have been developed for oxide supported bimetallic catalysts. In the first example, we demonstrate that Rh-W single atom pairs on Al₂O₃ exhibit a bifunctional reaction mechanism for alkene hydroformylation that allows 1000X activity enhancement and 50% selectivity enhancement as compared to Rh single atom catalysts. In the second example, it will be shown that the addition of < 1:100 mol fraction of Pt or Rh to supported Cu nanoparticles results in drastic stability enhancement under methanol synthesis reaction conditions through the mitigation of metal nanoparticle sintering. Through both examples we will highlight how multi-modal high surface area catalyst characterization can be correlated to model system studies using theory and surface science to develop structure-function relationships that explain the enhanced performance of bimetallic catalysts.

Phillip Christopher earned his B.S. in chemical engineering from University of California, Santa Barbara in 2006 and his M.S and Ph.D. in chemical engineering from University of Michigan in 2011 working with Prof. Suljo Linic. From 2011-2017 he was an Assistant Professor at University of California, Riverside. In 2017 he moved to the University of California, Santa Barbara where he is a Professor and Vice Chair for Undergraduate Affairs in the Chemical Engineering Department and the Mellichamp Chair in Sustainable Manufacturing. He serves as a Senior Editor for ACS Energy Letters. His research interests are in sustainable chemical conversion, heterogeneous catalysis by supported metals, dynamic behavior of catalysts, and photocatalysis by metal nanostructures. He has been given various awards including the Presidential Early Career Award for Scientists and Engineers (PECASE), AIChE CRE Division Young Investigator Award, and Ipatieff Prize from the ACS.