SYNTHESIS OF MONODISPERSE SUBMICRONIC GOLD PARTICLES BY THE POLYOL PROCESS

Monodisperse fine precious metal particles of uniform shape and high purity are increasingly needed in many areas of the electronics industry. The present study describes the formation of monodisperse quasi-spherical gold particles by reduction of tetrachloroauric acid (HAuCl4 . 3H(2)O) in a PVP-ethylene glycol solution. The average size of the obtained powders ranges from 0.1 to 0.4 mu m. The control of particle size, shape and degree of dispersion was achieved by varying the reaction parameters, such as the temperature of the medium, the amount of protective agent and the reaction time. The final gold powders were characterized by the classical anaylsis methods of solid state chemistry: X-ray diffraction analysis, scanning electron microscopy (SEM), chemical analysis.