Structural, Morphological and Optical Properties of ZnO, ZnO:Ni2+ and ZnO:Co2+ Nanostructures by Hydrothermal Process and Their Photocatalytic Activity

ZnO, ZnO:Ni2+ and ZnO:Co2+ nanoparticles (NPs) were prepared via hydrothermal process. The synthesized samples were characterized by using various techniques such as, FT-IR, powder XRD, SEM-EDX, TEM-SAED, UV-Visible, PL and BET. The as-synthesized ZnO, ZnO:Ni2+ and ZnO:Co2+ NPs exhibit strong physicochemical properties including in structural, surface morphology, chemical composition, surface area, optical and photocatalytic activity were comparatively investigated as function of Ni2+ and Co2+ doping. UV-Visible absorption spectra exhibit blue shifted in absorption edge of ZnO, ZnO:Ni2+ and ZnO:Co2+ NPs compared to bulk counterparts. The photocatalytic activity of the ZnO, ZnO:Ni2+ and ZnO:Co2+ NPs have been evaluated by monitoring the degradation of MeB and RhB dyes under UV light irradiation. In degradation efficiency, 84 and 93% of the MeB and RhB dyes is degraded in the presence of the ZnO:Ni2+ and ZnO:Co2+ photocatalyst under optimum experimental conditions. The rate of de-coloration of MeB and RhB dyes are detected by UV-Visible absorption spectroscopy and organic dye mineralization is confirmed by table of carbon study. In addition, the mechanism of the photocatalytic degradation of MeB and RhB dyes has been briefly discussed.