Photocatalytic Degradation of 2,4-Dichlorophenoxyacetic Acid Using Fe2O3/CeO2/Ag Composite Nanoparticles Under UV Light Irradiation

Fe2O3/CeO2/Ag composite nanoparticles were synthesized using a simple co-precipitation method. The as-synthesized samples were characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and energy dispersive X-ray spectroscopy (EDS). The photocatalytic activity of the as-synthesized samples was examined through photodegradation of 2,4-dichlorophenoxyacetic acid under UV light irradiation. The effects of pH, irradiation time, initial 2,4-dichlorophenoxyacetic acid concentration and the catalyst dose on the photocatalytic performance of Fe2O3/CeO2/Ag composite nanoparticles were all investigated by an optimization process. The photocatalytic kinetic data were analyzed using Langmuir-Hinshelwood model, suggesting the second-order reaction kinetics as the best model for 2,4-dichlorophenoxyacetic photodegradation. The photocatalytic activities revealed the highest photodegradation percentage for Fe2O3/CeO2/Ag composite nanoparticles with a degradation order as Fe2O3/CeO2/Ag (75.70%) > Fe2O3/CeO2 (36.28%) > CeO2 (26.92) > Fe2O3 (11.96). The adsorption equilibrium studies were examined by Langmuir and Freundlich isotherm models, indicating Langmuir isotherm with higher R2 as the most suitable model.