The synthesis of core-shell Fe3O4@mesoporous carbon in acidic medium and its efficient removal of dye

Magnetic core-shell Fe3O4@nSiO(2)@mSiO(2) nanoparticles were first synthesized with P123 as template in acid condition, which possess high BET surface area (839 m(2) g(-1)) and large pore volume (0.9 cm(3) g(-1)). Then Fe3O4@nSiO(2)@mSiO(2) nanoparticles were used as hard templates to synthesize Fe3O4@mesoporous carbon (Fe3O4@mC) with large surface area (971 m(2) g(-1)) and pore volume (1.4 cm(3) g(-1)). The high surface area and mesoporous structure of Fe3O4@mC favor its efficient adsorption of Rhodamine B in aqueous solution, which exhibited higher adsorption capacity of 198.9 mg g(-1) within 30 min than the previous reports on magnetic mesoporous graphitic carbon and magnetic mesoporous resin. The superparamagnetic property of Fe3O4@mC made it easily separated by an external magnetic field and reused after ethanol extraction. The rapid and efficient adsorption of dye together with their ease in separation and regeneration suggests that Fe3O4@mC composites have great potential applications in environmental abatements. (C) 2014 Elsevier Inc. All rights reserved.