Colloidal Au single-atom catalysts embedded on Pd nanoclusters
This study aims to design an efficient Au single-atom catalyst (SAC) for aerobic glucose oxidation and obtain a clear structure–activity relationship of the catalyst at the atomic level. Gold-containing bi- or multi-metallic catalysts are widely used in many important chemical processes. Engineering the electronic structure of surface atoms and downsizing the catalysts to single atoms are challengeable issues to enhance the intrinsic activity. Here we report an effective and versatile synthesis of colloidal Au/Pd SACs by using a facile successive reduction method. The prepared colloidal Au/Pd SACs exhibit a significantly improved catalytic activity (up to 17 times) for glucose oxidation over that of Au nanoclusters (NCs) with a similar size. High-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) analysis and density functional theory (DFT) calculation reveal that the presence of low-coordinated and negatively charged single Au atoms on Pd clusters is responsible for the excellent catalytic performance.