We are developing materials-generalizable chemical tools for controlling the facet structure, composition, and surface ligand environment of metal nanoparticles at the atomic scale.
For example, particular challenges exist for bimetallic nanomaterials composed of two metals with differing reactivity. Fine control over the location and relative concentration of both metals in these materials is essential for tuning catalyst performance, but differing reactivity in the elemental (reduced) state generally correlates with dissimilar chemistry for the ionic metal precursors. Therefore, creative new approaches are needed to differentially control the relative rates of reduction of the two metal ion precursors, and we have made important contributions in this area. Our group is also pioneering an innovative methodology for using fundamental electrochemical methods in combination with electrochemically-driven nanoparticle growth in a well-controlled chemical environment to understand redox transformations and the evolution of materials under the complex conditions of colloidal nanoparticle synthesis. Synthesis is central to chemistry, and the new materials and synthetic tools that result from this work will have broad-reaching impacts well beyond the field of catalysis. Just as many years of research have built up a solid foundation of fundamental reactions for the field of organic chemistry and molecular synthesis, the field of materials chemistry is still awaiting the fundamental chemical understanding required to fully enable predictable materials synthesis.