Green synthesis of silver oxide nanoparticles: Eco-friendly approach for sustainable solutions

The study explores the synthesis and characterization of silver oxide nanoparticles (Ag₂O) using leaf extract as a reducing agent, focusing on their antimicrobial and photocatalytic properties. X-ray diffraction (XRD) analysis showed that the leaf extract did not alter the crystalline phase of Ag₂O but affected its crystallite size and defect density. The diffractograms displayed peaks at: 2θ = 32.83°, 38.08°, 54.95°, 65.50°, and 68.83°, corresponding to the (111), (200), (220), (311), and (222) Bragg planes, respectively. The average Crystallite size (D) ranged from 15 to 40 nm, influenced by leaf extract concentration. Scanning electron microscopy (SEM) revealed that higher leaf extract concentrations reduced particle size from 100 nm to 10 nm, promoting aggregation. Fourier-transform infrared spectroscopy (FTIR) spectra confirmed the presence of functional groups on Ag₂O NPs and leaf extract, with bands attributed to metal-oxygen bond vibrations, C-O bond vibrations, and hydroxyl groups. UV-Vis spectroscopy showed broad absorption bands in both the visible and UV regions, with a reduced band gap (Eg) and increased Urbach energy (Eu) as the leaf extract concentration rose. Antimicrobial tests demonstrated the effectiveness of the Ag₂O NPs against both gram-positive and gram-negative bacteria, with minimum inhibitory concentrations (MICs) between 6.25 and 25 μg/ml. Photocatalytic tests revealed lower efficiency for Ag₂O NPs synthesized with leaf extract, with dye degradation yields ranging from 68 % to 87 %. The study highlights the potential of eco-friendly synthesized Ag₂O NPs for antimicrobial and photocatalytic applications in water purification and environmental catalysis.