Eco-Friendly Synthesis of MgO Nanoparticles: Influence of Precursor Concentration on Structural and Morphological Properties

Abstract

This study presents an eco-friendly green synthesis of magnesium oxide nanoparticles (MgO NPs) using Prunus persica leaf extract, investigating the critical role of precursor concentration (0.15–0.4 M) in tuning their structural, morphological, and optical properties. XRD confirmed the formation of a pure cubic MgO phase, with crystallite size increasing from 10.83 nm to 36.14 nm as precursor concentration rose. SEM revealed that 0.3 M yielded well-defined, spherical nanoparticles (~87 nm) The 0.3 M precursor concentration is optimal because it balances nucleation and growth, allowing phytochemicals to effectively cap Mg²⁺ ions—producing uniform, well-crystallized, defect-free MgO nanoparticles with the highest stability and bandgap (5.40 eV), while other concentrations resulted in agglomeration. EDX verified near-stoichiometric Mg:O ratios at 0.3 M, and FTIR confirmed biomolecule-assisted synthesis. UV-Visible analysis showed a strong absorption peak near 214 nm, with the optimal bandgap of 5.40 eV achieved at 0.3 M. These findings highlight 0.3 M as the ideal precursor concentration for synthesizing high-quality, stable MgO NPs via this sustainable route - offering promising potential for catalytic, biomedical, and environmental applications.