Acid-induced synthesis of polyvinyl alcohol-stabilized selenium nanoparticles

A simple wet chemical method, employing sulphuric acid, has been developed to synthesize polyvinyl alcohol (PVA)-stabilized selenium nanoparticles from an aqueous sodium selenosulphate precursor. The method is capable of producing spherical selenium nanoparticles in a size range of about 20–80 nm, under ambient conditions. The synthesized nanoparticles can be separated easily from the aqueous sols by a high-speed centrifuge and can be re-dispersed in an aqueous medium by an ultra-sonicator. The effect of concentration of sodium selenosulphate, PVA and acid, as well as the nature of the acid used, on the size of the selenium nanoparticles has been studied. The synthesized selenium nanoparticles have been characterized by UV–visible optical absorption spectroscopy, x-ray diffraction, thermogravimetric analysis, differential scanning calorimetry, dynamic light scattering, atomic force microscopy, scanning electron microscopy and transmission electron microscopy techniques.