One-step, size-controllable synthesis of stable Ag nanoparticles

摘要

A simple one-step process was developed for the preparation of stable Ag nanoparticles with high yield. Direct solvothermal treatment of an ethanol solution of AgNO3 and dodecanethiol (DT) resulted in the formation of Ag nanoparticles. X-ray powder diffraction (XRD) analysis indicated that the solid was composed of fcc-structured metal Ag. Infrared (IR) spectroscopy analysis demonstrated the presence of DT in the products. Transmission electron microscopy (TEM) showed that the particle size could be tuned from 5 nm to 100 nm by changing the synthesis parameters. The samples were stable (no irreversible precipitation) in the solid state for more than 8 months and could be redispersed into nonpolar organic solvent (cyclohexane) to form stable colloidal dispersions. A possible formation and size evolution mechanism is proposed.