A facile one-pot solvothermal method to produce superparamagnetic graphene-Fe3O4 nanocomposite and its application in the removal of dye from aqueous solution

A superparamagnetic graphene-Fe3O4 nanocomposite (G/Fe3O4) was synthesized by a facile one-pot solvothermal method. The nanocomposite G/Fe3O4 prepared by the new method was firstly used as an adsorbent to remove dye for water pollution remediation. In comparison with G/Fe3O4 prepared by the in situ chemical coprecipitation, the newly prepared G/Fe3O4 had a higher adsorption efficiency for the dye. The adsorption characteristics of the nanocomposite adsorbent were examined using the organic dye pararosaniline as the adsorbate. The adsorption kinetics, adsorption capacity of the adsorbent, and the effect of the adsorbent dosage and solution pH on the removal efficiency of pararosaniline were investigated. The adsorption capacity of G/Fe3O4 for pararosaniline was evaluated using the Freundlich and Langmuir adsorption isotherm models. The G/Fe3O4 hybrid composite can be easily manipulated in magnetic field for desired separation, leading to an easy removal of the dye from polluted water. The G/Fe3O4 hybrid composite would have a great potential in removing organic dyes from polluted water. (C) 2012 Elsevier B.V. All rights reserved.