Sustainable synthesis of ZnO and FexOy nanoparticles and their nanocomposite ZnFe2O4: Comprehensive characterization and applications in antioxidant activity and antibiotics degradation efficiency
Johar Amin Ahmed Abdullah, Hamdi Ali Mohammed, Chaima Salmi, Zarah Alqarni, Salah Eddine Laouini, Antonio Guerrero, Alberto Romero
Abstract
This study focuses on developing and evaluating eco-friendly nanoparticles, specifically Fe x O y NPs , ZnO NPs , and a ZnFe 2 O 4 nanocomposite (NC), for potential applications in environmental remediation and biomedicine. The nanoparticles were synthesized and characterized using X-ray diffraction (XRD), which revealed their crystalline structures with sizes of 20.3 nm for Fe x O y NPs , 22.1 nm for ZnO NPs , and 10.9 nm for ZnFe 2 O 4 NC. Fourier-transform infrared (FTIR) spectroscopy identified functional groups, while UV–visible spectroscopy determined band gap energies of 2.35 eV, 3.38 eV, and 2.68 eV for Fe x O y NPs, ZnO NPs , and ZnFe 2 O 4 NC, respectively. Morphological analysis via scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed that Fe x O y NPs have cubic, hexagonal, and tetragonal forms, ZnO NPs are hexagonal nanorods, and ZnFe 2 O 4 NC has a hexagonal-faced cubic structure. Antioxidant activity, assessed through the DPPH assay, revealed that ZnFe 2 O 4 NC had the highest potency. Additionally, under sunlight irradiation, ZnFe 2 O 4 NC demonstrated superior degradation of the antibiotic cephalexin (96 % within 30 min) compared to Fe x O y NPs (58.2 %) and ZnO NPs (52 %), with respective kinetic rate constants of 0.109 min −1 , 0.029 min −1 , and 0.025 min −1 . These results highlight the nanoparticles’ potential for environmental and biomedical applications.