Direct Synthesis of Bimetallic Pd₃Ag Nanoalloys from Bulk Pd₃Ag Alloy

Abstract

We report a transformative, all inorganic synthesis method of preparing supported bimetallic Pd₃Ag alloy nanoparticles. The method involves breaking down bulk Pd₃Ag alloy into the nanoparticles in liquid lithium, converting metallic Li to LiOH, and transferring Pd₃Ag nanoparticles/LiOH mixture onto non-water-soluble supports, followed by leaching off the LiOH with water under ambient conditions. The size of the resulting Pd₃Ag nanoparticles was found narrowly distributed around 2.3 nm characterized by transmission electron microscope (TEM). In addition, studies by X-ray diffraction (XRD), extended X-ray absorption fine structure (EXAFS) spectroscopy, and X-ray absorption near edge structure (XANES) spectroscopy showed that the resulting Pd₃Ag nanoparticles inherited similar atomic ratio and alloy structure as the starting material. The synthesized Pd₃Ag nanoparticles exhibited excellent catalytic activity toward hydrogenation of acrolein to propanal