Ligand Engineering of Dithiolate-Protected Au ₂₄ Pt Nanoclusters for Improved Thermocatalytic Activity

Thiolate-protected gold (Au) nanoclusters (NCs) are a well-established class of model NCs that have been extensively studied as catalysts for various reactions. However, many Au NCs feature surfaces completely passivated by ligands, leaving no exposed metal sites to serve as active centers. To address this issue, researchers have searched for methods to remove the ligands. However, simply introducing weakly bound ligands often compromises the structural stability of the NCs. In this study, we identified a novel Au NC that remains stable even with relatively weakly bound thiolate ligands by reinforcing the staple motifs through the introduction of dithiolate ligands. This Au NC exhibits excellent CO oxidation activity at relatively low temperatures, because the ligands can dissociate under relatively mild conditions. These findings show that advanced ligand engineering, beyond the metal core structure, significantly affects catalytic activity, providing a robust strategy for the design of diverse metal NC catalysts.