Professor Louise Berben
Department of Chemistry
Director, Center for Direct Conversion of Captured CO2
Associate Editor, Chemical Society Reviews
University of California, Davis
“Pre-equilibrium Metal Hydride Formation as a Strategy to Enhance Rate and Lower Overpotential in Electrocatalysis”
In this talk I will discuss metal carbonyl clusters (MCC’s) that have delocalized bonding and electronic structures that can serve as models for the regime of nanoparticle (electro)catalysts. The intermediate size of these clusters falls within the nanoscale while their synthesis and characterization is performed using the powerful characterization tools of molecular chemistry to enable a thorough characterization of structures and reactivity using tools such as single crystal X-ray diffraction and cyclic voltammetry (CV). Studies on the electrochemistry of large MCC’s have shown that their heterogeneous electron transfer, diffusion properties, and reactivity with protons are characteristic of nanomaterial and heterogeneous electrocatalysts.
Specifically, the chemistry of [Co13C2(CO)24]4- and [Co11C2(CO)23]2- will be described in this presentation. For large Co clusters, protonation of the cluster following electron transfer occurs at a rate of 10^9 s-1 and this drives a pre-equilibrium kinetics for the overall reaction mechanism. The fast hydride formation rate lowers the overpotential for catalysis by over 100 mV. And the effect of the pre-quilibrium hydride formation kinetics enhances the overall rate for formate formation by 5 orders of magnitude – relative to the expected rate derived from thermodynamic correlations. Formate formation is observed at a rate of 10^3 s-1 at just 10 mV of overpotential and with high selectivity.
Louise Berben
Louise Berben was born in Sydney, Australia. She received a Bachelor of Science degree with 1st class honors from The University of New South Wales in 2000, and in 2005 was awarded a Ph.D. from the University of California Berkeley for research undertaken with Professor Jeffrey Long. In 2006 Louise began postdoctoral research with Professor Jonas Peters at the California Institute of Technology and in July 2007, moved with the Peters research group to the Massachusetts Institute of Technology. In July 2009, Louise joined the faculty at the University of California Davis where her research program focuses primarily on synthetic and physical inorganic chemistry.
331 Smith Hall