Recent progress in the electrocatalytic applications of thiolate-protected metal nanoclusters

Ultrasmall metal nanoclusters (NCs) with atomic precision possess a size range between individual atoms and plasmonic nanomaterials. These atomically precise materials represent an emerging class of nanocatalysts, offering unique opportunities to explore electrocatalytic properties and establish precise structure-property correlations at the atomic scale. Among the large number of metal NCs that are stabilized by various ligands, thiolate-protected metal NCs are a particularly prominent class for electrocatalytic investigations. Recent experimental and theoretical studies have demonstrated the significant potential of these materials in enhancing various electrocatalytic reactions, including hydrogen evolution, oxygen reduction and CO₂ reduction reactions. However, comprehensive and in-depth discussions regarding their catalytic properties, particularly from a theoretical standpoint, are limited and require further explorations. In this review, we focus on the recent progress in thiolate-protected metal NCs in the field of electrocatalysis. The influences of structure, ligand, doping and interface control on their electrocatalytic activity/selectivity and the reaction mechanisms are discussed. Importantly, the perspectives we propose regarding future research endeavors are expected to offer valuable references for subsequent investigations in this area.