Synthesis and photocatalytic activity studies of Silver-Nitrogen co-doped ZnO-Fe2O3 nanocomposites for the degradation of Methylene blue under UV-Visible region

Abstract

The binary systems of ZnO-Fe₂O₃ nanocomposites were synthesized by a precipitation method with aqueous solutions of Fe and Zn nitrate, whereas nitrogen-doped ZnO-Fe₂O₃, silver-doped ZnO-Fe₂O_3, and silver-nitrogen co-doped ZnO-Fe₂O₃ nanocomposite were prepared by solid-state reaction. The structure and bandgap of the composites were studied using X-ray diffraction (XRD) and UV-visible diffuse reflectance spectroscopy (UV–vis). An aqueous model pollutant Methylene blue (MB) dye solution was used to evaluate photocatalytic degradation activities of the nanocomposites under visible light irradiation. Doping photocatalyst significantly increased the effectiveness of the photocatalyst in reducing bandgap energy. So 2.05 eV is the lowest energy, which is for Ag/N co-doped ZnO-Fe₂O₃ photocatalysts. Results of the experiment that involved the photocatalysts revealed that Methylene blue degradations of 45.11%, 47%, 51%, and 64.5% in 180 min under light radiation using ZnO-Fe₂O₃, Ag-doped ZnO-Fe₂O₃, N-doped ZnO-Fe₂O_3, and Ag/N co-doped ZnO-Fe₂O₃, respectively. The doped photocatalysts were all superior to the undoped ZnO-Fe₂O₃. The efficiency of Ag/N co-doped ZnO-Fe₂O₃ photocatalysts was higher on the photodegradation of MB at optimum PH, the load of Methylene blue photocatalyst which is 78%.