A simple method to synthesize modified Fe3O4 for the removal of organic pollutants on water surface

► Fe3O4 was prepared by a partial oxidation of Fe2+ in air without N2 gas protection. ► Different morphologies of Fe3O4 were obtained via adjusting the alkali source. ► Modified Fe3O4 can easily be synthesized by interaction between COO− and FeOH. ► Sodium oleate modified Fe3O4 is both super-hydrophobic and lipophilic. ► Modified Fe3O4 shows an important application in the removal of organic pollutants.