Versatile fabrication of the magnetic polymer-based graphene foam and applications for oil–water separation

The magnetic polymer-based graphene foam (MPG) for oil–water separation was fabricated by the synergistic effects of the deposition of Fe3O4 nanoparticles on graphene sheets and the self-assembly of graphene on polyurethane (PU) sponge. Graphene sheets were assembled on the surface of PU skeletons using ferrous ions as reducing agent, which can improve the adhesion of graphene on PU skeletons. The resulting MPG exhibited superhydrophobicity and superoleophilicity with the water contact angle of 158 ± 1° and the oil contact angle of 0°. A broad variety of oils and organic solvents can be removed from oil–water mixtures under manipulation by a magnet bar with high absorption capacity and selectivity. Significantly, the MPG can remain high absorption capacity for oil-water separation after several absorption/desorption-cycles, demonstrating its good reusability. Therefore, the findings of this study offered a facile approach for the cleanup of pollution by crude oil, petroleum products, and toxic organic solvents.