SYNTHESIS SILVER NANOPARTICLES AND ITS APPLICATION FOR WASTEWATER TREATMENT: CATALYTIC AND PHOTOCATALYTIC DEGRADATION METHYLENE BLUE

Abstract

This paper aims to propose a simple, eco-friendly method for obtaining colloidal solutions of silver nanoparticles (Ag NPs) by using of contact non-equilibrium low-temperature plasma in presents carboxymethyl cellulose (CMC) as a stabilizing agent and investigation on the decolorization of representative cationic phenothiazine dye in presence of nanocatalysts. Silver nanoparticles were prepared in aqueous AgNO3 solution by using of contact non-equilibrium low-temperature plasma in the present of carboxymethyl cellulose as capping agent. Ultraviolet–visible (UV) spectroscopy, X-ray diffraction, zeta potential, DLS analysis and SEM were used to study the formation and properties of silver nanoparticles. Measurements of optical spectra showed that the surface plasmon resonance was localized around 410-418 nm when the reaction mixture exposed to plasma for 1-5 min. The nanoparticles exhibited a good catalytic reduction for methylene blue dye in the presence of NaBH4. It followed pseudo-first order kinetics with a rate constant of 0.16 min−1. The catalytic degradation reaction was completed (98-99%) within 25 min. The photocatalytic activity of the synthesized silver nanoparticles was examined by degradation of methylene blue under sunlight irradiation. Synthesized silver nanoparticles were effectively degrading the dye nearly 98% at 70-72 h of exposure time.