The influence of polyvinylpyrrolidone(PVP) upon the formation of platinum-silica heterogeneous nanocomposite particles using chemical reduction process

초록

The chemical reduction of platinum (Pt) ions allows the preparation of heterogeneous Pt-silica (Pt-SiO2) nanocomposite particles, with amino (NH2) groups on the surface of SiO2 nanoparticles serving to bind the Pt nanoparticles. The Pt nanoparticles that formed on the surfaces of the SiO2 nanoparticles had an average diameter of ca. 3 nm. The dimensions and degrees of aggregation of the Pt nanoparticles on the SiO2 surface were influenced by the concentration of polyvinylpyrrolidone (PVP), the reducing agent, and the molar ratio of the reducing agent to Pt in the reaction medium. In addition, the functional groups present on the surfaces of the SiO2 nanoparticles had a profound influence on the coverage of the Pt nanoparticles. When NH2 groups were present on the surfaces of the treated SiO2 nanoparticles, the number of immobilized Pt nanoparticles increased upon the PVP concentration.