NSF Award
2404378
With the support of the Macromolecular, Supramolecular and Nanochemistry Program in the Division of Chemistry, Frank Zamborini and his research group at the University of Louisville will study electrochemical methods for synthesizing metal structures containing fewer than 200 atoms, called nanoclusters. Nanoclusters represent an important class of nanomaterials, serving as the foundations of nanotechnology. To date, metal nanoclusters have been made and purified in solution, typically are transferred to a solid conductive support for their use, and examined by expensive methods that are time-consuming and operated by highly trained users. The Zamborini group proposes to controllably make metal nanoclusters directly on a conductive support in pure form and examine them by their recently developed method, which is simple, economical and efficient. Commonly made metal nanoclusters have a wide distribution in the number of atoms in the nanocluster, but this work aims to make nanoclusters with the same size and same number of atoms. This would allow the group to better understand and tailor their properties for a specific use. One application is for catalyzing chemical reactions that are important in the chemical industry and in renewable energy strategies, such as would be deployed in developing batteries, fuel cells, electrolyzers, and solar cells. This research will provide interdisciplinary research training to undergraduate and graduate students on an exciting material to prepare them for careers in nanotechnology. The Zamborini group will promote science to high school and middle school students through online and in person events to share the excitement science with these students.<br/><br/>Under this award, the Zamborini research group of the University of Louisville will use electrochemistry for synthesizing, characterizing, and patterning a unique class of materials known as atomically-precise nanoclusters (APNCs), which are clusters of metal containing fewer than 200 atoms bonded with ligand stabilizers. Their fundamental properties and reactivity can be fine-tuned by controlling the number of atoms and type of atoms in the APNCs, including alloys. To date, they have been synthesized and purified in solution and characterized by expensive methods such as electron microscopy, mass spectrometry, and x-ray spectroscopy. The Zamborini group will electrodeposit APNCs of controlled size from metal ions in the presence of phosphine and phosphonium ligands by controlling the nucleation density and the stabilizer/metal ion ratio. They will add other metals controllable by antigalvanic replacement reactions. This will lead to a high coverage of metal/alloy APNCs on the electrode surface that will be characterized for size, coverage, and composition by electrochemistry, which is very simple, low cost, and high throughput. This will improve fundamental understanding of their properties for potential use in industrial processes and renewable energy strategies. The Zamborini group will also develop a hydrogel scanning probe tip to controllably pattern APNCs and nanoparticles on electrodes by electrodeposition within a nanoscale gel. If successful, these studies will enhance understanding of electrochemistry within nanoscale hydrogels and the properties of patterned nanostructures for applications in catalysis and sensing.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
