From Local Strain to Global Reactivity: Surface Microstructures of Gold Nanoparticles Regulate the Adsorption and Activation of Small Molecules

In this study, we examined the relationship between the surface strain characteristics of Au nanoparticles and the adsorption and activation of reactants using aberration-corrected transmission electron microscopy and density functional theory. The Au nanoparticle surface displayed macroscopic stability coupled with local dynamic distortions, featuring regions of both tensile and compressive strain. Tensile strain regions exhibited electron enrichment, whereas compressive strain regions exhibited electron depletion, thereby enhancing surface charge polarization. The adsorption and activation of O₂ molecules were significantly enhanced in tensile strain regions compared to that in the standard Au surface. CO molecules preferentially adsorbed at electron-enriched sites, with the adsorption strength increasing as the strain magnitude increased. Water adsorption on the Au surface resulted in increased negative charge via charge transfer. These findings elucidate the interplay between geometric and electronic structures in surface strain architectures and provide insights for designing catalysts with regulated adsorption sites for small-molecule reactions, offering strategies for precise catalyst synthesis and efficient design.