In Situ Observation of Active Surface Etching in Gold Nanoplates: Evidence for Intermediate Ligand Effects

作者：Qian Wang, Guangyu He, Yingming Pu, Xudong Peng, Hongyu Chen · 发表于：Journal of the American Chemical Society · 年份：2025 · DOI：10.1021/jacs.5c16137 · 被引用次数：5 · 研究领域：Nanowire Synthesis and Applications、Gold and Silver Nanoparticles Synthesis and Applications、Molecular Junctions and Nanostructures

We report the in situ observation of active surface etching in Au nanoplates using liquid-cell TEM. By analyzing the distinctive etching modes and in combination with our previous ex situ etching studies, we infer and substantiate the mysterious ligand behaviors: (1) the ligand plays dominant roles in etching, and its passivation is neither static nor uniform; (2) the ligand-deficient active sites and ligand-rich passivated sites are gradually and dynamically developed; and (3) the wavelike behavior of the etched nanoplate edges highlights the critical role of the dynamic diffusion of reactants. Comparisons among different thiol-based ligands confirm the generality of these conclusions. Finally, we integrate our hypotheses on the effects of ligands and reactant diffusion in kinetic Monte Carlo simulations. The fact that the main experimental trends are reproduced in silico strongly supports the proposed mechanisms of active surface etching.