%0 Journal Article
%T Effect of Additives on Characterization and Photocatalytic Activity of /ZnO Nanocomposite Prepared via Sol-Gel Process
%A Shahram Moradi
%A Parviz Aberoomand Azar
%A Sanaz Raeis Farshid
%A Saeed Abedini Khorrami
%A Mohammad Hadi Givianrad
%J International Journal of Chemical Engineering
%D 2012
%I Hindawi Publishing Corporation
%R 10.1155/2012/215373
%X TiO2/ZnO nanocomposites were prepared by the sol-gel method with and without addatives such as carboxy methyl cellulose (CMC), poly(ethylene glycol) (PEG), polyvinylpyrrolidon, (PVP), and hydroxylpropylcellulose (HPC). The characteristics of the prepared TiO2/ZnO nanocomposites were identified by IR spectra, X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS) methods. The additives have a significant effect on the particle size distribution and photocatalytic activity of TiO2/ZnO nanocomposites. The photocatalytic activity of the synthesized nanocomposites was investigated for decolorization of methyl orange (MO) in water under UV-irradiation in a batch reactor and the results showed that the photocatalytic activity of the nanocomposites have been increased by CMC, PEG, PVP, and HPC, respectively. SEM has shown that the particle size distribution of TiO2/ZnO nanocomposite in the presence of HPC was better than the other samples. 1. Introduction Azo dyes constitute the largest group of coloring materials in the textile industry [1¨C3]. Release of these substances in nature is the largest source of pollution for natural ecosystems. In recent decades, semiconductor photocatalyst TiO2 has been investigated as one of the most promising candidate for a photocatalyst and it has been attracted due to its potential application in removing of all types of organic pollutants in water [4¨C6]. In order to improve the photocatalytic activity and the response into visible part of the spectrum, TiO2 doping with metal ions or metal oxides has been applied [1, 2]. Several methods on the preparation of TiO2/ZnO were reported, such as solid-state method, impregnation method, and chemical coprecipitation method [7¨C9]. Another method is the sol-gel method that has significant advantages such as, high purity, good uniformity of the powder microstructure, low-temperature synthesis, and easily controlled reaction condition and therefore it has been used for preparing of TiO2/ZnO nanocomposite [4, 7, 10¨C12]. In this work, TiO2/ZnO nanocomposites were prepared by the sol-gel method in presence and absence of CMC, PEG, PVP, and HPC as additives. The synthesized nanocomposites were characterized by means of XRD, SEM, EDS, and IR spectroscopy. Since the particle size is an important parameter in photocatalytic activity, the effects of mentioned additives have been surveyed on the particle size distribution. The photocatalytic activity of TiO2/ZnO nanocomposites were assessed for decolorization of methyl orange (MO) in water under
%U http://www.hindawi.com/journals/ijce/2012/215373/