β-Cyclodextrin assisted one-pot synthesis of mesoporous magnetic Fe304@C and their excellent performance for the removal of Cr （VI） from aqueous solutions

Mesoporous magnetic Fe304@C nanoparticles have been synthesized by a one-pot approach and used as adsorbents for removal of Cr （IV） from aqueous solution. Magnetic iron oxide nanostructured materials encapsulated by carbon were characterized by scanning electron microscope （SEM）, nitrogen adsorption and desorption, X-ray diffraction （XRD） and Fourier transform infrared （FTIR） spectroscopy. The adsorption performance of the nanomaterial adsorbents is tested with the removal of Cr （IV） from aqueous solution. The results reveal that the mesoporous magnetic Fe304@C nanospheres exhibit excellent adsorption efficiency and be easily isolated by an external magnetic field. In comparison with magnetic Fe304 nanospheres, the mesoporous magnetic Fe304@C exhibited 1.8 times higher removal rate ofCr （VI）. The mesoporous structure and an abundance of hydroxy groups on the carbon surface may be responsible for high absorbent capability.