Enhanced Visible-Light Driven Photocatalytic Activity of Ag@TiO2 Photocatalyst Prepared in Chitosan Matrix

Abstract

Ag doped TiO(2)photocatalysts (Ag@TiO2) were prepared with an aim to extend the absorption range of TiO(2)into the visible region, for tentative application under solar irradiation. Photocatalyst synthesized by the novel method using chitosan for reduction of Ag(+)to Ag(0)nanoparticles was compared to similar catalysts previously reported. The photocatalytic activity of Ag@TiO(2)obtained by a simple novel method was evaluated based on degradation of salicylic acid as a model compound. The higher activity under visible irradiation can be attributed to the surface plasmon resonance and suppression of the electron-hole recombination when deposition of Ag nanoparticles on TiO(2)was achieved using chitosan. The photocatalysts were characterized by X-ray diffraction (XRD), Raman spectroscopy, transmission electron microscopy (TEM), high resolution TEM (HRTEM), energy dispersive X-ray spectroscopy (EDXS), selected area diffraction (SAED), and diffuse reflectance spectroscopy (DRS). The photochromism of Ag was observed and explained.