Photocatalytic degradation of nitro and chlorophenols using doped and undoped titanium dioxide nanoparticles

Abstract

Pure and Ag-TiO2 nanoparticles were synthesized, with the metallic doping being done using the Liquid Impregnation (LI) method. The resulting nanoparticles were characterized by analytical methods such as scanning electron micrographs (SEMs), Energy Dispersive Spectroscopy (EDS), and X-ray diffraction (XRD). XRD analysis indicated that the crystallite size of TiO2 was 27nm to 42nm while the crystallite size of Ag-TiO 2 was 11.27nm to 42.52nm. The photocatalytic activity of pure TiO2 and silver doped TiO2 was tested by photocatalytic degradation of p -nitrophenol as a model compound. Ag-TiO2 nanoparticles exhibited better results (98% degradation) as compared to pure TiO2 nanoparticles (83% degradation) in 1 hour for the degradation of p -nitrophenol. Ag-TiO2 was further used for the photocatalytic degradation of 2,4-dichlorphenol (99% degradation), 2,5-dichlorophenol (98% degradation), and 2,4,6-trichlorophenol (96 degradation) in 1 hour. The degree of mineralization was tested by TOC experiment indicating that 2,4-DCP was completely mineralized, while 2,5-DCP was mineralized upto 95 percent and 2,4,6-TCP upto 86 percent within a period of 2 hours. Copyright © 2011 Hassan Ilyas et al.