Green Synthesis of ZnO Nanoparticles Using Azadirachta indica Leaf Extract for Rapid Catalytic Degradation of Organic Pollutants
J. Environ. Nanotechnol., Volume 15, No 2 (June 2026) pp. 151-161
Abstract
Green synthesis of zinc oxide nanoparticles (ZnO NPs) using plant extracts provides an environmentally sustainable alternative to conventional chemical synthesis methods. In this study, ZnO nanoparticles were synthesized using Azadirachta indica leaf extract and characterized using X-ray diffraction (XRD), UV–visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX). The synthesized nanoparticles exhibited uniform morphology with particle sizes below 100 nm. The catalytic performance of ZnO nanoparticles was evaluated for the degradation of organic dyes including methyl orange (MO), methylene blue (MB), and Congo red (CR). The results demonstrated high degradation efficiencies of 95.35% for MO, 97.82% for MB, and 98.29% for CR within short reaction times. In addition, the ZnO nanoparticles efficiently catalyzed the reduction of p-nitrophenol to p-aminophenol within 2–4 minutes in the presence of NaBH₄. The enhanced catalytic activity is attributed to the high surface area and active sites of the biosynthesized ZnO nanoparticles. These findings demonstrate that neem-mediated ZnO nanoparticles offer a cost-effective, rapid, and environmentally friendly catalytic system for the remediation of dye-contaminated wastewater.
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