Yolk-shell Fe3O4@MOF-5 nanocomposites as a heterogeneous Fenton-like catalyst for organic dye removal

Yolk-shell Fe3O4@MOF-5 nanocomposites were synthesized by utilizing a simple solvothermal method. The physicochemical properties of the yolk-shell Fe3O4@MOF-5 nanocomposites were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Brunauer?Emmett?Teller (BET) and vibrating sample magnetometer (VSM) methods. The nanocomposites had a catalytic yolk, a hollow cavity and a porous shell. The nanocomposites had relatively high specific surface area of 203 m2 g-1 and showed superparamagnetic property. The catalytic activities of the yolk-shell Fe3O4@MOF-5 nanocomposites were evaluated by using methylene blue dye as a model pollutant. It is demonstrated that the yolk-shell Fe3O4@MOF-5 nanocomposites as a heterogeneous Fenton-like catalyst exhibited excellent catalysis since the internal cavity provided a relatively stable micro-environment for the reaction of the active ?OH radicals and the pollutants on the basis of the confinement effect. Furthermore, the yolk-shell Fe3O4@MOF-5 nanocomposites could be lightly separated from the pollutant solution by an external magnetic field and maintained good catalytic activity after five recycles, indicating the good stability of the nanocomposites.

Automated summary

The yolk-shell Fe3O4@MOF-5 nanocomposites exhibited excellent catalytic performance, high specific surface area, superparamagnetic behavior, and remarkable stability in pollutant solutions.