Reactivity and Lability Modulated by a Valence Electron Moving in and out of 25‐Atom Gold Nanoclusters

Abstract

The emergence of atomically precise metal nanoclusters with unique electronic structures provides access to currently inaccessible catalytic challenges at the single‐electron level. We investigate the catalytic behavior of gold Au25(SR)18 nanoclusters by monitoring an incoming and outgoing free valence electron of Au 6s1. Distinct performances are revealed: Au25(SR)18− is generated upon donation of an electron to neutral Au25(SR)180 and this is associated with a loss in reactivity, whereas Au25(SR)18+ is generated from dislodgment of an electron from neutral Au25(SR)180 with a loss in stability. The reactivity diversity of the three Au25(SR)18 clusters stems from different affinities with reactants and the extent of intramolecular charge migration during the reactions, which are closely associated with the valence occupancies of the clusters varied by one electron. The stability difference in the three clusters is attributed to their different equilibria, which are established between the AuSR dissociation and polymerization influenced by one electron.

Ligand Engineering toward the Trade‐Off between Stability and Activity in Cluster Catalysis

“…These results indicate that 4-NP is more easily adsorbed on 2, which accounts for the superior activity of 2. [37,46] This study demonstrates that the electronic structure of a metal nanocluster can be modulated via the combination of ligands, and the catalytic performance can thus be improved.…”

“…For example, Zhu et al. reported that the stable 8‐electron [Au 25 (SCH 2 CH 2 Ph) 18 ] − showed lower catalytic activity than the unstable 7‐electron Au 25 (SCH 2 CH 2 Ph) 18 in the intramolecular hydroamination of 2‐ethynylaniline [37] . Therefore, the balance between stability and activity of cluster catalysts should be taken into consideration in terms of pursuing high catalytic performance.…”

Ligand Engineering toward the Trade‐Off between Stability and Activity in Cluster Catalysis

“…Because both clusters have enough space for the adsorption of 4‐NP, the influence of steric effects is believed to be minor in terms of the calculation of Gibbs free energy, which suggests that it is mainly affected by the electronic structures. These results indicate that 4‐NP is more easily adsorbed on 2 , which accounts for the superior activity of 2 [37, 46] . This study demonstrates that the electronic structure of a metal nanocluster can be modulated via the combination of ligands, and the catalytic performance can thus be improved.…”

Bioinspired Electron Polarization of Nanozymes with a Human Self‐Generated Electric Field for Cancer Catalytic Therapy

“…This further accelerates the production and movement of electrons, thereby boosting the POD-like activity of COF-CNT. [22] The occurrence of polarization is not affected by the direction of COF-CNT in the electric field. Furthermore, the degree of surface polarization increases with an increase in the voltage of the electric field, which can be benefited from the self-driven TENG with a high voltage output.…”