Design of AgM Bimetallic Alloy Nanostructures (M = Au, Pd, Pt) with Tunable Morphology and Peroxidase-Like Activity

Bimetallic alloy nanoparticles (NPs) exhibit unique optical and catalytic properties that are dependent on their morphology and composition. In this paper, a general and facile way was developed to prepare Ag-related bimetallic alloy NPs with hollow/porous structures, including AgAu, AgPd, and AgPt. The formation of the alloy structures is evidenced by high-resolution transmission electron microscopy (TEM), scanning transmission electron microscopy−energy-dispersive X-ray analysis (STEM-EDX) mapping, and ultraviolet−visible−near-infrared (UV−vis−NIR) absorption spectra. AgM alloy NPs exhibit peroxidase-like activity. A unique composition dependence is found and can be used to tailor the catalytic activity. In addition to the recent discoveries about peroxidase mimetics on Fe 3 O 4 NPs and sheetlike FeS nanostructures, our findings suggest a new type of candidate as peroxidase mimics. Furthermore, for noble metals, apart from size and shape, tailoring the composition poses another effective way to tune the catalytic activity.