Method for Visible Light-Induced Photocatalytic Degradation of Methylparaben in Water Using Nanostructured Ag/AgBr@m-WO3.

An efficient method of photocatalytic degradation of methylparaben in water using Ag nanoparticles (NPs) loaded AgBr-mesoporous-WO3 composite photocatalyst (Ag/AgBr@m-WO3 ), under visible light is presented. In this process, quantification of methylparaben in water was carried out by high-performance liquid chromatography (HPLC) and the HPLC results showed a significant reduction of methylparaben in water due to the enhanced of photocatalytic degradation efficiency of Ag/AgBr@m-WO3 . For the material synthesis, highly ordered mesoporous-WO3 (m-WO3 ) was initially synthesized by sol-gel method and AgBr nanoparticles (NPs) were subsequently introduced in the pores of m-WO3 , and finally, the Ag nanoparticles were introduced by light irradiation. The enhanced photocatalytic degradation of methylparaben in water is attributed to the formation of surface plasmonic resonance (SPR) due to the introduction of Ag NPs on the surface of the catalyst. Also, the formation of heterojunction between AgBr and mesoporous-WO3 in Ag/AgBr@m-WO3 significantly inhibited the recombination of light-induced electron-hole pairs in the semiconductor composite. The morphological and optical characterizations of the synthesized photocatalysts (Ag/AgBr@m-WO3 ) were carried out using SEM, TEM, XDR, N2 adsorption-desorption, UV-VIS diffuse reflectance spectroscopy (DRS). Also, the photocatalytic studies using radical scavengers were carried out and the results indicated that O 2 · - is the main reactive species.