Solar Photocatalytic Activity of Nanocrystalline ZnO Obtained from Different Precursors

Abstract

In present study, ZnO photocatalysts were successfully synthesized by thermal decomposition of different precursors. Thermal decomposition temperatures of precursors were obtained by thermogravimetric analysis. The synthesized ZnO photocatalysts were characterized for their crystalline phase, surface morphology and band gap, respectively by powder X-ray diffraction, scanning electron microscopy and diffuse reflectance spectroscopic methods. Chemical analysis of synthesized ZnO photocatalysts was performed for Zn(II) content. Photocatalytic activity of ZnO photocatalysts was evaluated under the solar irradiation on crystal violet dye in aqueous solution. The results of experiments showed that ZnO synthesized from zinc carbonate consists of higher photocatalytic activity than ZnO synthesized from other precursors, which is even higher than bench mark Degussa P-25 TiO2 photocatalyst. ZnO synthesized from zinc carbonate is further used for mineralization of dyes from three different effluents.