Room Temperature Synthesis of Nanostructured ZnO: Active Visible Photocatalyst in the Degradation of Methylene Blue
Amine El Farrouji
*
Laboratoire de Chimie Appliquée et Environnement, Faculté des Sciences Ibn Zohr, Agadir, Morocco and Laboratoire de Chimie de Coordination et Catalyse, Faculté des Sciences Semlalia, Marrakech, Morocco.
Rachid Mohamed Tchalala
Laboratoire de Chimie de Coordination et Catalyse, Faculté des Sciences Semlalia, Marrakech, Morocco.
Abderrahim Chihab Eddine
Laboratoire de Chimie Appliquée et Environnement, Faculté des Sciences Ibn Zohr, Agadir, Morocco.
Ahmad Mehdi
Laboratoire de Chimie Moléculaire et Organisation du Solide, Université Montpellier, Montpellier, France.
Larbi El Firdoussi
Laboratoire de Chimie de Coordination et Catalyse, Faculté des Sciences Semlalia, Marrakech, Morocco.
Mustapha Ait Ali
Laboratoire de Chimie de Coordination et Catalyse, Faculté des Sciences Semlalia, Marrakech, Morocco.
*Author to whom correspondence should be addressed.
Abstract
Nanostructured ZnO was prepared using a facile solution-phase method at room temperature without need to calcination. Oxidation of zinc sulfate by sodium hypochlorite in the presence of polyethylene glycol (PEG) and sodium hydroxide (NaOH) gave pure nanostructured zinc oxide (ZnO-NPs). The structure and physicochemical properties of the material were determined by X-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy (IR), Energy Dispersive X-ray Spectroscopy (EDS), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), UV–Vis diffuse reflectance and their optical Properties. ZnO particles were successfully distributed in two-dimensional sheet with a nanometric thickness and a random distribution. The activity was evaluated for photocatalytic degradation of methylene blue (MB) by a study of experimental conditions such as the effect of the mass of the catalyst, the effect of the initial concentration of the dye and the effect of the volume of the oxidizing agent. The kinetics of the reaction follow a pseudo-first order.
Keywords: Nanostructured ZnO, Nanosheets, band-gap, photocatysis, methylene blue