Preparation of Fe3O4@Prussian blue core/shell composites for enhanced photo-Fenton degradation of rhodamine B

Fe3O4@PB core/shell composites were prepared by a reactive-template method. They served as effective catalyst in photo-Fenton reaction toward rhodamine B degradation. [Display omitted] •Photo-Fenton reaction was performed on the surfaces of both Fe3O4 core and PB shell•k of Fe3O4@PB composite was 7.44 × 10−3 min-1, 1.5 times higher than that of Fe3O4 NC•Ea of Fe3O4@PB composite was 15.1 kJ/mol, 1.2 times lower than that of Fe3O4 NC•△H, △S and △G was 15.0 kJ/mol, 31.3 J/mol K and 5.56 kJ/mol•97.6 % of degradation efficiency was remained after the 5th cycle In this study, Fe3O4@Prussian blue (PB) core/shell composite was prepared via a reactive-template method. The morphological and structural characteristics of composite were carefully investigated by X-ray diffraction, transmission electron microscope, scanning electron microscope, Fourier transform infrared spectrometer and and X-ray photoelectron spectroscope. Their activity in photo-Fenton reaction was examined using rhodamine B (RhB) degradation as a model reaction, and the optimal degradation condition was determined to be 10 mg/L of RhB, 587 mM of H2O2, pH = 6.5 and 318 K. Rate constant of the reaction catalyzed by Fe3O4@PB composites was 7.44 × 10−3 min-1, about 1.5 times higher than that catalyzed by Fe3O4 nanoclusters (NCs). The activation energy of the reaction catalyzed by Fe3O4@PB composites was 1.2 times lower than that catalyzed by Fe3O4 NCs. Mechanism study indicated that OH played a dominating role in RhB degradation. In addition, Fe3O4@PB core/shell composites with a saturation magnetization of 33.4 emu/g were easily recycled via a magnet. Almost 97.6 % of degradation efficiency was remained after the 5thcycle, indicating their good reusability. This study suggested that Fe3O4@PB core/shell composite demonstrated a potential application for the removal of persistent organics from aquatic environments.