Author: B. Lavanya and Y. Aparna

DOI: http://doi.org/10.31788/RJC.2026.1949898

This study investigated the eco-friendly synthesis of iron oxide nanoparticles (Fe3O4 NPs) using Oxalis strictaleaf (OSL) extract. The Fe3O4 NPs were characterised using XRD, FESEM, FTIR, UV-Vis, and PL. XRDanalysisrevealed a cubic, crystalline phase with a crystallite size of 14.37 nm. FESEM images showed a rough, cauliflowerlike surface morphology, with particle sizes ranging from 100 - 120 nm. FTIR spectra indicated the presenceof various functional groups, confirming the formation and stabilisation of Fe3O4 NPs by phytochemicals in the OSLextract. UV-Vis spectroscopy showed a peak at 397 nm, and the energy band gap was calculated to be 2.77 eVusinga Tauc plot. The antifungal activity of the Fe3O4 NPs was evaluated against Aspergillus niger and Trichodermaasperellum, with inhibition zones observed at concentrations starting from 125 µg/mL. The photocatalytic activityof Fe3O4 NPs was investigated for the degradation of methylene blue dye under UV radiation, and pseudo-first-order kinetics were observed. The results show that Oxalis stricta-mediated synthesis is a simple, environmentally friendly, sustainable method for producing functional Fe3O4 nanoparticles that possess antifungal and photocatalyticproperties. The study contributes to ongoing research in green nanotechnology by presenting an environmentallyfriendly approach to the production of multifunctional nanomaterials whose applications include environmental remediation, wastewater treatment, and antimicrobial technologies, while laying the foundation for future studies onthe sustainable production of nanomaterials

Keywords: Green Synthesis, Iron Oxide Nanoparticles, Oxalis Stricta, Photocatalysis, Antimicrobial Activity.