Magnetic Fe3O4@C/Cu and Fe3O4@CuO core–shell composites constructed from MOF-based materials and their photocatalytic properties under visible light

Magnetic Fe3O4@C/Cu and Fe3O4@CuO nanocomposites with a core/shell structure have been successfully synthesized via direct calcinations of magnetic Fe3O4@HKUST-1 in different atmosphere (N2 and air). The morphology, structure, magnetic and porous properties of the as-synthesized nanocomposites were characterized by using scanning electron microscope (SEM), transmission electron microscopy (TEM), powder X-ray diffraction (PXRD), vibration sample magnetometer (VSM), and N2 sorption–desorption isotherms. The results show that the nanocomposite materials consist of a Fe3O4 core and a C/Cu (or CuO) shell. Fe3O4@C/Cu nanocomposites show more powerful photocatalytic activity for the degradation of methylene blue (MB) under visible light irradiation in the presence of H2O2 in comparison with Fe3O4@CuO nanocomposites and the most common photocatalyst titanium dioxide (TiO2), as well as the recently developed organic semiconductor graphitic carbon nitride (g-C3N4). Meanwhile, the catalyst is stable during the reaction and the high Ms value (39.2 emu g−1) of the as-prepared magnetic composites is favorable for the separation and recycling of the catalyst from the reaction media after the catalytic reactions.