Synthesis, characterization and photocatalytic activity of Ag–TiO2 nanoparticulate film

Abstract

Ag–TiO₂ nanoparticulate film was synthesized by dip coating followed by adsorption and photoreduction in UVA light, characterized by transmission electron microscopy, scanning electron microscopy, energy dispersive analysis of X-rays, glancing angle X-ray diffractometry and UV-Vis absorption spectrophotometry techniques. The data indicated the presence of TiO₂ particles of anatase phase of size varying from 5–15 nm, Ag nanoparticles of size varying from 10–20 nm, and also indicated the added visible light activity in Ag–TiO₂ nanoparticle films. Photocatalytic degradation of methyl parathion (O,O-dimethyl O-(4-nitrophenyl) phosphorothioate), a well known pesticide in aqueous solution was studied using Ag–TiO₂ nanoparticulate film and the data was compared with TiO₂ nanoparticulate film. Photocatalytic degradation reactions demonstrated pseudo first order behaviour. Methyl parathion was found to be degraded initially to paraoxon which further was degraded to p-nitrophenol, trimethyl ester of phosphoric acid, trimethyl ester of phosphothioic acid, and finally to phosphate ion. Minute amounts of carbon dioxide and acetaldehyde were also detected.