Computational and Experimental Elucidation of the Charge‐Dependent Acid‐Etching Dynamics and Electrocatalytic Performance of Au25(SR)18q(q = −1, 0, +1) Nanoclusters

Abstract Using thiolate‐protected Au 25 (SR) 18 nanocluster (NC) with different charge states as the test candidate, how the charge effect affects the etching dynamics of thiolate ligands in acid and the electrocatalytic performance is explored. The ab initio molecular dynamics (AIMD) simulations revealed the charge‐dependent reaction kinetics in acid, where the anionic and neutral Au 25 (SCH 3 ) 18 q (q = −1, 0) favorably react with the acid and partially remove the thiolate ligands via two‐step proton attack, while the cationic Au 25 (SCH 3 ) 18 + NC is acid‐resistant with no tendency for ‐SR removal. Density functional theory (DFT) calculations further predict that the dethiolated Au sites exhibit enhanced catalytic activity for CO 2 electroreduction to CO, with the anionic Au 25 − showing significantly superior activity. Acid etching and electrocatalytic experiments further confirmed partial removal of thiolate ligands in Au 25 (SCH 3 ) 18 q (q = −1, 0), with dethiolated Au 25 NCs showing enhanced catalytic performance in CO 2 electroreduction, particularly Au 25 − exhibiting better activity than Au 25 0 . This work revealed an interesting charge state‐mediated interface dynamics and electrocatalytic behaviors in Au 25 NCs, which can be applied to modulate the interface and catalytic properties of other atomically precise metal nanoclusters.