Photocatalytic Degradation of ۲,۴-Dichlorophenoxyacetic Acid Using Fe<SUB>۲</SUB>O<SUB>۲</SUB>/CeO<SUB>۲</SUB>/Ag Composite Nanoparticles under Ultraviolet

Background: The herbicide ۲,۴-dichlorophenoxyacetic acid (۲,۴-D) is used to control of agricultural pests (water and soil) and is among the most widely distributed pollutants in the environment. Methods: In this study, Fe۲O۳/CeO۲/Ag composite nanoparticles were synthesized using a simple coprecipitation method. The as-synthesized samples were examined using X-ray diffraction, field emission scanning electron microscopy, and X-ray analysis. The photo catalytic activity of the as-synthesized samples was examined through photo degradation of ۲,۴-dichlorophenoxyacetic acid (۲,۴-D) under ultraviolet irradiation. The effects of pH, irradiation time, initial ۲,۴-D concentration and catalyst dose on the photo catalytic performance of Fe۲O۳/CeO۲/Ag composite nanoparticles were investigated through an optimization process. The photo catalytic reaction kinetic data were analyzed using Langmuir-Hinshelwood model, and the absorption equilibrium was examined by Langmuir and Freundlich isotherm models. Results: The results suggested the second order reaction kinetics as the best model for ۲,۴-D photo degradation. Moreover, Langmuir isotherm with a higher R۲ was reported as the most suitable model. The photo catalytic activities revealed the highest photo degradation percentage for Fe۲O۳/CeO۲/Ag composite nanoparticles with a degradation order as Fe۲O۳/CeO۲/Ag (۷۵.۷۰%)>Fe۲O۳/CeO۲ (۳۶.۲۸%) >CeO۲ (۲۶.۹۲)>Fe۲O۳ (۱۱.۹۶). Conclusions: Based on the determination of nanomaterial efficiency, its components and photo catalytic properties, can be used to remove this contaminant and other toxic compounds.

کلیدواژه ها:

Fe۲O۳/CeO۲/Ag ، Photocatalytic performance ، Isotherm models ، ۲ ، ۴-dichlorophenoxyacetic