Synthesis and characterization of visible active Fe grafted ZnO nanocomposites for NBB degradation in water

Photocatalysis embraces prodigious ability as an efficient and sustainable oxidation technology for application in wastewater treatment. In general, a good photocatalytic material should have chemical stability, low production cost, and especially environment-friendliness characteristics. The present study involves the development of visible light active semiconductors by surface-grafted Fe(III) ions and bulk metal oxide. Fe-grafted ZnO nanocomposites were synthesized at two different temperatures. Initially, the precipitation-decomposition method was adopted for the ZnO preparation; later, surface of ZnO was grafted with Fe3+ ions at two different temperatures under basic condition. The prepared materials have been characterized by various characterization techniques such as X-ray diffraction (XRD), scanning electron microscope (SEM), High-resolution transmission electron microscope (HR-TEM), X-ray photoelectron spectra (XPS), diffuse reflectance spectra (DRS) and Photoluminescence (PL) study. The degree of electron-hole recombination decreased in Fe-modified ZnOs as evidenced by PL measurements. The prepared materials used for naphthol blue black (NBB) dye destruction under visible light, and found that Fe modification slightly enhances the degradation ability of the ZnO. DRS measurements confirm the higher absorbance at the visible region in Fe/ZnOs materials. The catalyst was found to be reusable. A suitable degradation mechanism is proposed for the destruction of Naphthol Blue Black (NBB) dye by Fe-grafted ZnO nanocomposites under visible light.