Green route to prepare zinc oxide nanoparticles using Moringa oleifera leaf extracts and their structural, optical and impedance spectral properties

This article investigates biosynthesis of zinc oxide (ZnO) nanoparticles (NPs) from Moringa oleifera leaves extract using an eco-friendly preparation method. The crystalline structure, optical properties, morphology and impedance characteristics of ZnO NPs were analyzed using impedance spectroscopy, powder X-ray diffraction (XRD), scanning electron microscopy, Fourier transform infrared spectroscopy (FTIR) and ultraviolet spectroscopy (UV-vis). The powder XRD pattern confirmed the crystallinity of the prepared samples as well as enabled determining their crystallite size and pure phase portion. The FTIR study confirmed the presence of functional groups responsible for reduction metal ions into ZnO NPs. UV-vis absorption spectra contained the absorption peak corresponding to ZnO NPs. Impedance spectroscopy of the prepared ZnO NPs revealed the grain boundaries in them and confirmed their semiconducting nature.