Size Transformation of the Au₂₂(SG)₁₈ Nanocluster and Its Surface-Sensitive Kinetics

Abstract

For many applications of well-defined gold nanoclusters, it's desirable to understand their structural evolution behavior under working conditions with molecular precision. Here we report the first systematic investigation on the size transformation product of Au22(SG)18 nanocluster under representative working conditions and highlight the surface effect on the transformation dynamics. Under thermal and aerobic conditions, the consecutive and pH dependent transformation from Au22 to both well-defined clusters and small Au(I)SR species were identified by the ESI-MS and UV-vis spectroscopy. By introducing perturbation on the Au22 surface, significant changes in the activation parameters were determined from the kinetic study of the Au22 transformation. This indicates the sensitivity of nanocluster transformation pathway the cluster surface. The systematic study on cluster transformation and sensitivity of cluster transformation to the surface revealed herein have significant implications for future attempts to design gold nanoparticles with adaptation to the working environment and the regeneration of active nanoparticles.

Understanding the Chemical Insights of Staple Motifs of Thiolate‐Protected Gold Nanoclusters

“…[ 25,26 ] AuNC protected by thiolates has also been used as model system in studying the size transformation of the cluster. [ 27 ] All these studies recognize that the most important merit of thiolates is their functions in imparting stability to the corresponding AuNCs. Previous theoretical studies mostly focused on the understanding of the central metal core of the cluster.…”

Structural Isomerization in Cu(I) Clusters: Tracing the Cu Thermal Migration Paths and Unveiling the Structure-Dependent Photoluminescence

“…Based on the same the intricate processes of phase transformations in bulk or nano-inorganic solids. Recently, HRESI-MS has been used to study the assembly mechanism of metal clusters, 18,[48][49][50] which is obviously unsuitable for investigating the isomeric transformation in clusters because they have the same composition. Liquid UV can be used to monitor the conversion process of isomers, 26,27,30,31 but unable to clarify the structures of the intermediates.…”

Sulfur-doped graphene anchoring of ultrafine Au25 nanoclusters for electrocatalysis

“…However, the significant surface under-coordinating nature of NCs tends to induce the sintering and aggregation of the clusters with formation of larger particles during reaction, considerably altering the experimental size-reactivity relationship. Hence, a crucial challenge to exploit the intrinsic catalytic properties of NCs [11] is to achieve cluster stability.…”