Synthesis and Characterization of ZnO:NiO Nanocomposites Prepared by Phyllanthus Emblica Fruit Extract Assisted Green Method

Abstract

We present the environment-friendly facile production of ZnO nanoparticles and ZnO: NiO nanocomposites by a completely green synthesis method using Phyllanthus emblica fruit extract as solvent as well as reducing agent. The existence of ZnO and NiO phases in the nanocomposites is confirmed by XRD analysis. Rietveld Refinement was performed to calculate the corresponding structural parameters. The average crystallite size is found in between 18 nm to 22 nm for the different phases present in all the samples. The microstructures of ZnO nanoparticles and ZnO:NiO nanocomposites were investigated by FE-SEM, displaying mixed morphology having a combination of quasi-spherical and hexagonal shape and the particle size varying from 20 nm to 120 nm. The existence of vibrational modes corresponding to ZnO and NiO phases is shown by Raman spectroscopy. Dielectric characteristics were examined as a function of applied electric field frequency, revealing a decrease in dielectric constant with NiO addition, which was ascribed to the creation of ZnO:NiO interfaces in the composites. Complex impedance analysis was used to confirm the effect of grain and grain boundary resistance on dielectric characteristics. Complex impedance analysis, which supports the predominance of grain boundaries in the conduction process, was used to confirm the effect of grain and grain boundary resistance on the dielectric characteristics.