ZnO nanoparticles with altered structural and optical traits by Cu and Li doping for elevated photocatalytic activity toward organic pollutants

Doping of copper and lithium on zinc oxide nanoparticles (NPs) has attracted a great deal of attention due to their morphological change, large surface-to-volume ratio, and enhanced physical properties. In this study, Cu-doped ZnO NPs (CZO) and Li-doped ZnO NPs (LZO) were synthesized by one-step hydrothermal method. The obtained nanostructures were characterized using analytical techniques such as XRD, UV-visible spectroscopy, FTIR, SEM, and TEM. The XRD analysis of CZO and LZO revealed hexagonal nanorod structures possessing a dominant peak at (101) hkl plane. From SEM imaging, it was observed that the doping concentration of Cu- and Li- onto the ZnO nanoparticles had an effect on the morphology and size of the obtained nanorods. EDAX analysis confirmed the presence of Cu and Li ions in the ZnO lattice structures. The photocatalytic degradation of CZO and LZO was performed using two dyes namely Rhodamine B and methylene orange under tungsten bulb light source. CZO and LZO showed a degradation of 56.51% +/- 0.61% and 63.97% +/- 0.02% for Rhodamine B; 45.68%+/- 0.39% and 40.01%+/- 0.045% of degradation was observed for methylene orange dye. [Graphical Abstract]