Phycosynthesis and photocatalytic degradation of methyl orange using silver nanoparticles synthesized by the Sargassum wightii

Abstract

The present study was demonstrated with simple and rapid synthesis of silver (Ag) nanoparticles using marine seaweed, Sargassum wightii. The nanoparticles of silver were formed by the reduction of silver nitrate to aqueous silver metal ions during exposure to the extract of marine seaweed S. wightii. The optical properties of the obtained silver nanoparticles were characterized using UV–visible absorption and room temperature photoluminescence. The X-ray diffraction results reveal that the synthesized silver nanoparticles are in the cubic phase. The existence of functional groups was identified using Fourier transform infrared spectroscopy. The morphology and size of the synthesized particles were studied with atomic force microscope and Scanning electron microscope measurements. Further, the photocatalytic degradation of methyl orange was measured spectrophotometrically by using silver as nanocatalyst under visible light illumination. The results revealed that biosynthesized silver nanoparticles using S. wightii was found to be impressive in degrading methyl orange.