Preparation and Optical Properties of Metal Nanoparticles

Abstract

Au nanoparticles embedded in poly vinyl alcohol (Au/PVA) films on slide glass substrates were prepared by a photoreduction technique. In the presence of ethylene glycol in the films, Au nanoparticles were effectively formed by the UV irradiation. The mean diameter of Au nanoparticles in PVA was estimated to be 37 nm. When the Au/PVA films were immersed in various types of alcohols with different refractive index (n_D), the surface plasmon resonance absorption peak were shifted toward a longer wavelength with increasing n_D of the alcohols. These properties are used for a new type optical sensor.