Design and Catalytic Application of Ag-Au Nanoprisms: Enhancing A3 Coupling Efficiency with Minimal Gold Concentration

Abstract

A novel bimetallic Ag-Au nanoprism incorporating trace levels of gold (ppm range) was synthesized via a wet-chemical method. The material was comprehensively characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM) mapping, X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). This new nanostructure exhibits a remarkable synergistic interaction between the silver nanoprism and meager amounts of gold, resulting in highly efficient catalytic activity for the A3 coupling reaction involving aldehydes, alkynes, and amines. The reaction proceeds efficiently in water at 60 ℃, accommodating a broad substrate scope and showcasing its versatility. Notably, the catalytic system achieves excellent performance even at ultralow gold loadings (80 ppm), highlighting its cost-effectiveness and sustainability. Furthermore, the catalyst demonstrates robust reusability, retaining its activity over four consecutive cycles in aqueous media.