Dual shelled Fe3O4/polydopamine hollow microspheres as an effective Eu(III) adsorbent

A facile method was developed to synthesize Fe3O4/polydopamine (PDA) dual shelled microspheres with a hollow interior. Since the final product was obtained by in situ polymerization of dopamine (DA) on the surface of a hollow Fe3O4 spherical template, the average size of the hybrid microspheres was tunable by manipulating both the Fe3O4 size and the PDA shell thickness. Due to the hollow interior and the compatible surface, the Fe3O4/PDA demonstrated excellent adsorption performance for Eu(III) ion removal (151.05 mg g(-1)) in aqueous solution. In comparison to pristine Fe3O4 hollow spheres, the dual shelled particles exhibited a faster adsorption dynamic process and a higher adsorption capacity for Eu(III) entrapment. Simultaneously, the Fe3O4/polydopamine (PDA) also exhibits a higher adsorption capacity for Eu(III) entrapment compared with that of other magnetic materials. This method was also effective for synthesizing other kinds of PDA shell encapsulated core/shell nanoparticles.