Adsorption behavior and mechanism of As(V) on magnetic FeO-graphene oxide (GO) nanohybrid composite material.

In this study, the magnetic FeO-graphene oxide (GO) nanohybrid composite material was prepared via the combination of the modified Hummer's method and coprecipitation. The morphology of the hybrid sample showed that the diffusion of FeO nanoparticles into the porous channels of mesoporous GO layers not only restricted the restacking of GO nanosheets but also prevented the leaching and agglomeration of magnetic nanoparticles. The result of the kinetic and isotherm studies that were performed to evaluate the adsorption mechanism showed a good fit with the pseudo-second-order kinetic and Langmuir isotherm models. The As(V) adsorption efficiency, H, of the GO/FeO nanohybrid composite material reached the maximum value of 99.37% after 60 min. The maximum adsorption capacity q of the GO/FeO nanohybrid material was 14.1 mg·g in an acidic aqueous solution (pH 1). The role and contribution of GO and FeO nanoparticles in adsorption and the improvement in As(V) adsorption efficiency were also investigated in further detail. The findings of this work suggested that the GO/FeO nanohybrid material could be widely applied for polluted water treatment.