Preparation, characterization and photocatalytic activity of Co-doped ZnO powders

ZnO powders with different Co(2+) doping concentrations (0, 0 5, 1, 3 and 5 mol%) were prepared by the hydrothermal method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM). UV-vis diffuse reflectance spectrometer, and photochemical reaction instrument The results show that the ZnO powders are hexagonal wurtzite structures and their crystallization decrease with the increase of Co(2+) doping concentration The products are spherical which have diameter of about 200 nm, and their absorption edge shift to longer wavelength with the increase of the Co(2+) concentration. The photocatalytic activities of the powders are evaluated using a basic organic dye, methyl orange (MO) Compared with undoped ZnO, It is found that the photocatalytic properties of the Co-doped ZnO have been improved greatly. When the doping concentration is 3 mol%, the degradation ratio of MO can reach 78% after reacting for 240 mm. (C) 2010 Elsevier B V. All rights reserved