Biosynthesis of Ag-doped ZnO Nanoparticles from MelonPeel Extract and Investigation of Their AntibacterialActivity

Abstract

This study was designed to synthesise zinc oxide (ZnO) and silver-doped zinc oxide (ZnO:Ag) nanoparticles using an aqueous extract of melon peels as a natural reducing and stabilising agent. For the first time, melon peel extract was used to produce both pure ZnO and Ag-doped ZnO nanoparticles at doping levels of 2% and 3%. The synthesised nanoparticles were characterised by FTIR, XRD, SEM, and EDX methods. XRD analysis revealed a hexagonal crystal structure in all samples, with crystallite sizes of 28.51 nm (ZnO), 26.06 nm (ZnO:Ag 2%), and 37.96 nm (ZnO:Ag 3%). FTIR results confirmed the incorporation of silver into the ZnO matrix. Scanning electron microscopy (SEM) showed mostly spherical particles, with ZnO:Ag 2% exhibiting welldefined crystallinity. EDX results confirmed the successful doping of ZnO with silver. The synthesis of ZnO:Ag 2% nanoparticles demonstrated significant antibacterial properties against Staphylococcus aureus, Bacillus cereus, and Escherichia coli, with photocatalysis revealing 85% degradation of methylene blue (MB).