Green synthesis and characterization of metallic nanoparticles with environmental applications

Abstract

Synthesis of silver and gold nanoparticles using Sargassum extract as a reducing and stabilizing agent is reported. The physicochemical characterization of nanoparticles was carried out by ultraviolet–visible spectroscopy, X-ray diffraction, and scanning electron microscopy. The results confirmed the synthesis of nanoparticles with a nanometer crystal size. Ultraviolet–visible spectroscopy analysis showed that the surface plasmon resonance was dependent on the experimental conditions. Increasing the concentration of the precursor salt led to an increase in the concentration of the synthesized nanoparticles. In the case of silver nanoparticles, a near-spherical morphology was observed with a size range between 20 and 60 nm. Gold nanoparticles, also near-spherical in shape, have a size of less than 50 nm. On the other hand, the photocatalytic properties of the nanoparticles were evaluated through the degradation of organic dyes. Gold nanoparticles showed higher efficiency and higher rate of degradation for methyl violet and malachite green.Graphical abstract