Properties of a Nanosilver–Silica Composite Synthesized with Different Molecular Weights and Polyvinylpyrrolidone Concentrations

Abstract

Well-dispersed nanosilver particles were synthesized by a chemical reduction method, where silica was treated with amino groups, mercapto groups, and polyvinylpyrrolidone (PVP) as a dispersant. Transmission electron microscopy (TEM) images showed that both the concentration and the molecular weight of PVP considerably affected the size of the silver nanoparticles. The average size of the silver nanoparticles prepared with amino-treated silica increased with increasing PVP concentration, whereas the size of the silver nanoparticles prepared with mercapto-treated silica was not affected by the PVP concentration.As the molecular weight of PVP increased, the average size of the silver nanoparticles also increased. The number of silver particles formed with mercapto-treated silica was larger, and the size distribution was narrower than those formed from aminotreated silica.