Ligation in Data-Driven Synthesis Studies of Nanoparticles—A Case Study of Phosphine-Stabilized Gold

Nanoparticles are promising materials for electrocatalysis due to their large surface area to facilitate reactions with diverse properties tunable by composition, geometry, and surface chemistry. However, the informed synthesis of precise shapes and sizes of nanoparticles is still out of reach due to limited theory relating synthesis parameters directly to outcomes. Previous data-driven studies have aimed to map the potential energy surface of specific systems of nanoparticles by generating and calculating the energies of thousands of reasonable structures. This talk will show that it is crucial to include surface-stabilizing ligands as an additional factor in studies of solution-based synthesis. In solution-based synthesis, environmental ions and ligands can energetically stabilize specific sizes and shapes. Phosphine-stabilized gold is considered as a test system and DFT calculations are performed for particles with and without ligands, producing a first of its kind database containing 11,000 structures for Au_n(PH₃)_m (n≦12, m≦n). The study found that the addition of phosphines had an effect on the thermodynamic stability, bonding, and electronic structure. New ground state cluster geometries were stabilized that do not exist in the pure gold system. Further, the addition of phosphine introduced steric effects that induced an earlier non-planar transition size than previously predicted for bare clusters. Our work highlights the importance of considering the environment in the prediction of nanoparticle morphology and functionality, which adds complexity and necessitates data-driven methodologies and advancements. This talk will detail the study as well as promote the corresponding database of 11,000 phosphine-stabilized gold clusters that is available to the public for further use.