Well-defined bimetallic nanomaterials provide a platform for structure-activity studies of catalytic transformations at the intersection of macroscopic single crystal model surfaces and working catalysts, thereby filling the critical “pressure and materials gap” in catalyst design from fundamental principles.
Large nanoparticles (50-100 nm) with precision surfaces are ideal analogues of model single crystals used in ultrahigh vacuum (UHV) surface science experiments and computational studies because of their ordered atomic arrangement. These nanoscale model materials have the added advantage of also possessing sufficient surface area to operate as catalysts with a measurable turnover rate. Our group studies these highly precise “nanoscale model surfaces” under realistic catalytic conditions by tracking structure-function relationships resulting from clearly defined modifications of surface atomic arrangement, elemental composition, and the presence of molecular adsorbates. With this platform, we have the ability to validate predictions from UHV and computational surface science under working catalytic conditions.
Our group recently demonstrated proof of concept for this approach in the context of oxygen-assisted coupling reactions of alcohols. Building on this precedent, we are studying selective oxidation and hydrogenation reactions relevant to the production of sustainable high-energy-density fuels and bio-based chemicals from biomass feedstocks. Importantly, large, well-defined, nanoscale materials are uniquely suited to enable the introduction of materials complexity to the low-pressure UHV environment. We also study colloidal metal nanostructures using spectroscopic and temperature-programmed reaction techniques under UHV conditions, further facilitating the translation of fundamental reactivity to functional catalyst design.
Robertson, D. D.; Personick, M. L. “Growing Nanoscale Model Surfaces to Enable Correlation of Catalytic Behavior Across Dissimilar Reaction Environments.” Chem. Mater. 2019, 31, 1121-1141. [Perspective/Review]
King, M. E; Personick, M. L. “Iodide-Induced Differential Control of Metal Ion Reduction Rates: Synthesis of Terraced Palladium-Copper Nanoparticles with Dilute Bimetallic Surfaces.” J. Mater. Chem. A 2018, 6, 22179-22188.
Robertson, D. D.; King, M. E.; Personick, M. L. “Concave Cubes as Experimental Models of Catalytic Active Sites for the Oxygen-Assisted Coupling of Alcohols by Dilute (Ag)Au Alloys.” Top. Catal. 2018, 61, 348-356.