This contribution reports on the biosynthesis of nickel oxide and zinc oxide nanoparticles (NiO-NPs & ZnO-NPs) via a natural extract from Moringa Oleifera leaves as an effective chelating and/or oxidizing/reduction agent of nickel nitrate hexahydrate and zinc nitrate hexahydrate. The structural and optical properties of these two types of semiconductors obtained in a similar procedure are investigated using X-rays Diffraction (XRD), Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR), diffuse reflectance UV-Visible-NIR and Photoluminescence (PL) techniques. The structural analysis shows the formation of pure cubic NiO-NPs and pure wurtzite ZnO-NPs with an average crystallite size of 17.80 nm and 10.81 nm respectively. Their band gaps, calculated from the diffuse reflectance analysis were found to be 4.28 eV and 3.35 eV respectively.

This contribution provides the synthesis and characterization of nickel oxide nanoparticles (NiO NPs) which were prepared by green synthesis method using natural extract oranges peel skin (Peel Citrus Sinensis) as an effective bio-oxidizing/bio-reducing agent. The effect of different calcination temperatures on the size of the NiO NPs was investigated. The prepared nanoparticles were characterized by various techniques such as X-rays diffraction (XRD) results indicated that all the samples have a face-centered cubic (FCC) structure and confirmed the presence of high degree of crystallinity nature NiO NPs. The functional group composition of NiO NPs were investigated by using attenuated total reflection-Fourier transform infrared (ART-FTIR), Photoluminescence (PL), and Scanning electron microscopy (SEM).