Engineering PEG-Modified Fe2O3 Nanostructures for Enhanced Photocatalytic Degradation of Pesticide and Antibiotic Pollutants in Water.

Pesticide and pharmaceutical contaminants in water have become an important environmental challenge because of their persistence, toxicity, and limited removal by conventional treatment methods. In this work, iron oxide nanoparticles (Fe2O3NPs) and polyethylene glycol-coated iron oxide nanoparticles (Fe2O3@PEG NPs) were synthesized and tested for photocatalytic degradation of organic pollutants in aqueous media. The obtained materials were characterized using XRD, FTIR, UV-Vis spectroscopy, and SEM analyses. The XRD patterns confirmed the formation of crystalline hematite (α-Fe2O3), with average crystallite sizes of 21.26 nm for Fe2O3 and 19.02 nm for Fe2O3@PEG. FTIR spectra indicated successful PEG coating, whereas UV-Vis analysis revealed direct band-gap energies of 2.09 and 2.00 eV, respectively. Photocatalytic performance was investigated through the degradation of chlorpyrifos and amoxicillin under UV light. The Fe2O3@PEG material showed better activity, reaching 95.84% degradation of chlorpyrifos after 120 min and 95.03% removal of amoxicillin within 60 min. Kinetic results were consistent with a pseudo-first-order model. The improved efficiency of the modified material was mainly related to better dispersion, enhanced surface interaction, and lower charge recombination.