PHOTOCATALYTIC MECHANISMS OF SILVER NANOPARTICLES IN DEGRADATION OF ORGANIC DYES:A NANOPHYSICS PERSPECTIVE

Abstract

This paper will explore the photocatalytic processes of silver nanoparticles (AgNPs) in degradation of organic dyes with a nanophysics approach. AgNPs synthesized chemically and biologically were characterized by UV-Vis spectroscopy, TEM, XRD and FTIR in order to describe their optical and morphological properties as well as structural properties. AgNPs were discovered to generate localized surface plasmon resonance (LSPR) behavior that is at the heart of their photocatalytic activity in visible light. AgNPs were shown to degrade methylene blue (MB), rhodamine B (RhB), and methyl orange (MO) rapidly (pseudo-first-order) with apparent rate constants of 0.016 to 0.028 min -1 when irradiated by visible light. The photocatalytic improvement was observed to be due to the separation of charge as a result of plasmon, direct transfer of hot-electron, and the production of reactive oxygen species (ROS). It was observed in the comparative analysis that AgNPs performed better than the traditional TiO 2 and ZnO photocatalysts because of the high light absorption and effective electron-hole interactions. The degradation rate and stability of AgTiO2 and Ag-TiO 2 and other hybrid types were facilitated by enhancing the plasmon-semiconductor coupling. The results have established the significance of nanophysical characteristics, such as the size of a particle, morphology, and surface charge, in maximization of photocatalytic activity. The current piece of work illuminates the potentials of AgNPs in wastewater treatment as a plasmonic nanoreactor, and brings about an insight into the physical basis of the nanoscale photocatalysis.