Influence of optical radiation on the silver nanoparticles formation

Abstract

In this work, the synthesis of spherical silver nanoparticles in aqueous solution was performed by photostimulated reduction. A research of the laser exposure time effect of silver colloids on the optical response and nanoparticles concentration in the studied solution was carried out. The influence of long time exposure (up to 6 days) of silver colloid by LEDs with radiation wavelengths of 525 and 633 nm on their geometric, spatial and optical parameters was studied. It has been shown that prolonged irradiation of silver colloid leads to changes in the nanoparticles morphology, which is confirmed by a change in the colloidal color and appearance of additional plasmon absorption peaks on the spectral scale. The formation of silver nanoparticles and nanoprisms in aqueous solution was confirmed by spectrophotometry and transmission electron microscopy. Modelling of absorption spectra of triangular silver nanoparticles by the discrete dipole approximation approach, implemented in DDSCAT software, was carried out.. The electromagnetic radiation of the optical range is a promising tool that can be effectively used for both synthesis and modification of optical and spatial parameters of silver nanoparticles.