Green Method, Optical and Structural Characterization of ZnO Nanoparticles Synthesized Using Leaves Extract of M. oleifera

ZnO nanoparticles (ZnO-NP) present innovative optical, electrical, and magnetic properties that depend on specific characteristics, e.g., size, distribution, and morphology. Thus, these properties are essential to address various applications in areas such as electronics, medicine, energy, and others. In addition, the performance of this ZnONP depends of their preparation which can be done by chemical, physical, and biological methods. Meanwhile, nowadays, the main interest in developing ZnO-NP synthesis through biological methods bases on the decrease of use of toxic chemicals or energy applied to the procedures, making the process more cost-effective and environmentally friendly. However, the large-scale production of nanoparticles by green synthesis remains a big challenge due to the complexity of the biological extracts used in chemical reactions. That being the case, the preparation of ZnO-NP using Moringa oleifera extract as an alternative biological agent for capping and reduction in synthesis was evaluated in this work. Then, the results based on the analysis of the optical and structural characterization of the ZnO-NP obtained by employing UV-Vis, DLS, zeta potential, XRD, ATR-FTIR, and FE-SEM indicate mostly the presence of spherical nanosized material with a mean hydrodynamic diameter of 47.2 nm measured by DLS and a mean size diameter of 25 nm observed with FE-SEM technique. Furthermore, in FE-SEM images a homogeneous dispersion and distribution is observed in the absence of agglutination, agglomeration, or generation of significant lumps of the ZnO-NP. The XRD analysis showed that heat annealing induced the crystallite size favoring their monocrystallinity. Those obtained data confirm the synthesis of ZnO-NP and the absence of impurities associated with organic compounds in the annealed samples. Finally, those results and low-cost production present to the synthesized ZnO-NP by this biological method as a useful material in several applications.

Automated summary

ZnO nanoparticles have innovative properties for various applications. Utilizing biological methods for synthesis reduces the use of toxic chemicals, making the process more cost-effective and environmentally friendly.