Abstract:
Water plays a crucial role in every animate life. Nanomaterials are efficient at removing pollutants such as organic dyes and heavy metals from wastewater. Organic contaminants are often needed to be removed with adequate techniques. In this study, the photocatalysts of Cadmium oxide nanoparticles (CdO NPs), and Nickel oxide nanocomposites (Ni-CdO NCs) were successfully synthesized through green method in order to investigate their degradation performance against Rhodamine B (RhB) dye. The crystal structure, morphology, functional groups, and degradation efficiency of as-synthesized photocatalysts were characterized using x-ray diffraction (XRD), Fourier transform Infrared (FTIR), Scanning Electron Microscope (SEM) and UV-Visible spectroscopic techniques respectively. The highly sharp and intensive peaks XRD patterns attributed to the cubic structure for Cadmium oxide nanoparticles (CdO NPs) and Ni doped Cadmium oxide nanocomposites (Ni-CdO NCs) structures with decreasing average crystal size from 0.33 nm to 0.311 nm. Accordingly, particle size brought about to narrow the band gap energy of CdO NPs and Ni-CdO NCs from to 2.19 eV to 2.03 eV, respectively. The FT-IR spectrum showed that the absorption peaks are emerged corresponding to Cd–O, Ni-O and C–N plane deformation in Ni-CdO NCs. Among the synthesized photocatalysts, CdO NPs and Ni-CdO NCs exhibited the best degradation efficiency of 97.987 and 98.678 %, respectively at pH 6, 5 ppm concentration of dye, 0.30 g of catalyst load, and 180 min irradiation time. Moreover, the kinetics photodegradation of RhB dye at optimum conditions followed pseudo-first order reaction with the rate constant of 1.95 x 10-2 min-1. The results suggested that, the developed treatment method for this particular dye could be applicable for the treatment of wastewater samples containing acidic dyes