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

초록

The immobilization of gold nanoparticls onto the silica surface was carried out by chemical reduction process. Amino groups (-NH2) were used to bind the gold nanoparticles onto the silica surface. Ethanol/water mixture was used as a solvent. The resultant particles of these reductions were characterized through transmission electron microscopy and UV-vis. spectroscopy. The size of immobilized gold nanoparticle was controlled by the variation of PVP concentrations ( 0.1 wt%, 0.2wt% 0.3wt% and 0.5 wt% ) using short polyvinyl chained PVP (M.W.=10,000) and PVP molecular weights (M.W.= 10,000, 29,000, 40,000 and 58,000) when reducing agent to hydrogen tetrachloroaurate (Ⅲ) hydrate (HAuCL4?nH2O) molecular ratio of solution was fixed to 2.0 : 1.0 . On basis of the experimental results, the influence of PVP concentration, PVP molecular weight and the concentration of reducing agent upon the formation of gold-silica heterogeneous nanocomposite particles were discussed.