One-pot Sonochemical Synthesis of Hg–Ag Alloy Microspheres from Liquid Mercury

Abstract

Metallic mercury has always attracted much attention in various fields because of its unique characteristic of forming amalgams. Here, different phases of pure crystalline Hg–Ag amalgam microspheres are synthesized by ultrasonically reacting liquid mercury with an aqueous solution of silver nitrate. Sonicating different molar ratios of liquid metallic Hg with AgNO3 results in the formation of pure crystalline phases of solid silver amalgams with uniform morphology. The resulting Hg–Ag amalgams from various compositions after sonication are physically characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS) and Differential Scanning Calorimetry (DSC). The XRD of the amalgams obtained from the molar ratios of Hg:Ag (1:1.5) and Hg:Ag (1.5:1 and 2:1) match the Schachnerite and Moschellandbergite phases, respectively, whereas the Hg–Ag amalgam prepared from a 1:1Hg:Ag molar ratio results in a mixture of the Schachnerite and Moschellandbergite phases. The obtained amalgam microspheres are between 6 and 10µm in size. The detailed thermal and chemical behaviour of the Ag–Hg systems is also investigated.