Highly regenerable mussel-inspired Fe3O 4@Polydopamine-Ag core-shell microspheres as catalyst and adsorbent for methylene blue removal

We report a facile method to synthesize Fe3O 4@polydopamine (PDA)-Ag core-shell microspheres. Ag nanoparticles (NPs) are deposited on PDA surfaces via in situ reduction by mussel-inspired PDA layers. High catalytic activity and fast adsorption of a model dye methylene blue (MB) at different pH values are achieved mainly due to the presence of monodisperse Ag NPs and electrostatic interactions between PDA and MB. The as-prepared Fe3O4@PDA-Ag microspheres also show high cyclic stability (>27 cycles), good acid stability, and fast regeneration ability, which can be achieved efficiently within several minutes by using NaBH4 as the desorption agent, showing great potentials in a wide range of applications. \ua9 2014 American Chemical Society.Peer reviewed: YesNRC publication: Ye