Green synthesis of zinc oxide nanoparticles by Azadirachta indica L. and its optimization and characterizations

Abstract

The green synthesis of zinc oxide nanoparticles (ZnO NPs) using Azadirachta indica (Neem) provides an eco-friendly and sustainable alternative to conventional chemical synthesis methods. This study investigates the optimization of key synthesis parameters,
including temperature, pH, zinc precursor salt and reaction time, to achieve ZnO NPs with desirable physicochemical properties. Neem leaf extract being rich in bioactive phytochemicals, served as the reducing and stabilizing agent. The synthesized ZnO NPs were characterized using UV-visible spectrophotometry, Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM), measurements. The
optimal synthesis conditions were found at 60°C, pH 8, using zinc acetate with a reaction time of 4 hours. Characterization results revealed that the ZnO NPs had an average size of 30-70 nm, with good stability and a narrow size distribution. The findings highlight the potential of Neem as a viable green resource for the synthesis of ZnO NPs, with implications for various biomedical and industrial applications.