Nanocrystalline ZnO Thin Film for Photocatalytic Purification of Water

摘要

A thin film ZnO nanostructured catalyst exhibited a significantly greater superiority for the photodegradation of 2,4,6-TCP in water over photolysis via irradiation with UV of 254 nm wavelength. This ZnO photocatalyst was prepared via Zn metal evaporation and deposition on a glass sheet followed by calcination ature from 350 to 500 ℃ and the calcination time from 1 to 2h shows via SEM photography a decrease of ZnO nanoparticales sizes sheet followed by calcination (oxidation). Increasing the calcination temperature from 350 to 500 ℃ and the calcination time from 1 to 2h shows via SEM photography a decrease of ZnO nanoparticales sizes as well as the shape of their crystals finer needles, for which the crystallinity enhances as revealed by XRD. 2,4,6-Trichlorophenol was used as a model pollutant in water. Its photolysis using UV only or photocatalysis using UV irradiation in presence of the ZnO thin film catalyst indicated aromatic intermediates, which suffered of Cl by OH, addition of OH in a bare carbon in the aromatic ring, whereas in Photocatalysis deeper oxidation products, e.g., quinones and hydroquinones were also formed.