The UV absorption spectra of all AgNPs solutions were determined on an Optizen 2120UV spectrophotometer with 2 nm resolution at room temperature.
The spectrum wavelengths were recorded between 200 and 700 nm and a glass cuvette with 1 cm optical path was used.
The studies of size and morphology of the nanoparticles were performed by transmission
electron microscopy (TEM) using Philips CM120 microscope operating at up to 120 KV. Samples for
TEM studies were prepared by placing drops of the silver nanoparticles solutions on carbon-coated TEM grids and allowing the solvent to slowly evaporate under vacuum for 30 min at room temperature.