Plant-Mediated Synthesis of TiO₂ Nanoparticles: Comparative Study of Structural, Antibacterial, and Anticorrosive Properties

This study reports the green synthesis of titanium dioxide (TiO₂) nanoparticles using Monoon longifolium leaf extract and a comparative evaluation of two synthesis approaches, namely ultrasonication (TiO-A) and magnetic stirring (TiO-B). The formation and physicochemical properties of the nanoparticles were confirmed through UV–Visible spectroscopy, FTIR, XRD, FESEM, EDX, and TGA analyses, revealing nanoscale crystalline structures with effective surface functionalization by plant-derived biomolecules. Optical studies indicated characteristic UV absorption, while XRD confirmed phase purity and nanocrystalline nature. Morphological and elemental analyses further validated the successful formation of TiO₂ nanoparticles. The antibacterial activity demonstrated moderate efficacy against both Gram-positive and Gram-negative bacteria, with TiO-A showing comparatively higher inhibition due to improved surface characteristics. Additionally, anticorrosion studies using the weight-loss method revealed that nanoparticle-coated mild steel exhibited reduced corrosion rates in acidic, basic, and neutral media, with maximum protection observed under neutral conditions. The enhanced performance is attributed to the formation of a stable protective layer and effective surface coverage by nanoparticles. Overall, the findings highlight that plant-mediated TiO₂ nanoparticles, particularly TiO-A, possess promising antibacterial and anticorrosive properties, making them suitable for biomedical and environmental applications.