PHOTOCATALYTIC ACTIVITY OF ZnO PARTICLES PREPARED FROM VARIOUS PRECURSORS BY HYDROTHERMAL PROCESS
Keywords:
Photocatalytic activity, ZnO, zinc Precursors, Hydrothermal processAbstract
In this work, ZnO particles with different morphologies and surface areas have been prepared by hydrothermal process using various zinc precursors. The obtained ZnO powders were characterized for phase, morphology, and surface area by X-ray powder diffraction (XRD), Scanning Electron Microscopy (SEM), and Brunauer-Emmet-Teller (BET), respectively. The effect of the zinc precursors on the photocatalytic activity of the resultant ZnO was evaluated through a study of the decomposition of the methylene blue solution under UV-lamp irradiation. It was found that the pure ZnO in the zincite structure was obtained from all precursors which were precipitated by NaOH or KOH under hydrothermal reaction at 150oC for 6h. The results show that the type of precursors hadplayed a significant role on the morphology and surface area of the obtained ZnO which had affected its photocatalytic activity. From the results, the rod-like ZnO particles prepared from zincnitrate and precipitated by NaOH showed the highest photocatalytic activity compared with the other precursors.
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