Zeta Potential and Hydrodynamic Radii of Silver Sulfide Nanoparticles in a Colloidal Solution with Mercaptopropylsilane

The dependence of the zeta potential and hydrodynamic radii of silver sulfide nanoparticles (Ag 2 S) in an aqueous colloidal solution on the concentration of stabilizer 3-mercaptopropyltrimethoxysilane (MPS) is determined. A model for the structure of a surface layer of Ag 2 S nanoparticles coated with MPS is proposed that explains the observed dependence and the extrema on it. It is found that the values of the zeta potential and the hydrodynamic radii of the Ag 2 S nanoparticles depend substantially on the means of creating an excess of silver ions in the solution. This dependence is explained by the dynamics of the formation of a stabilizer layer on the surface of nanoparticles.