Combined dual-metal templates for fabrication of magnetic hierarchical porous carbon for highly efficient removal of 4-nitrophenol

摘要

A combined dual-metal template method was used to prepare magnetic hierarchical porous carbon (MHPC). In this work, agar was selected as the carbon source and chelating agent, and Zn(NO3)(2)center dot 6H(2)O and FeCl3 simultaneously served as the sources of the dual-metal center ions and as structure-directing agents. Zn2+ and Fe3+ ions were coordinated with agar via a chelate-assisted co-assembly route. The mixture was subsequently converted into an iron-zinc-carbon composite. Finally, the asprepared composite was calcined to form MHPC. X-ray powder diffraction demonstrated the existence of alpha-Fe in the MHPC, and the magnetic properties of MHPC were determined to be 84.1 emu/g. Nitrogen adsorption measurements revealed that MHPC had a high surface area of 764.54 m(2)/g, and a total pore volume of 0.61 cm(3)/g. The adsorption test results indicated that MHPC has a high adsorption capacity for 4-nitrophenol (227.27 mg/g) and that it is easy to isolate from aqueous solution under the assistance of an external magnetic field.