Facile Synthesis of Uniform Microspheres Composed of a Magnetite Core and Copper Silicate Nanotube Shell for Removal of Microcystins in Water

The hierarchical microspheres of Fe3O4@copper silicate nanotube (Fe3O4@CSNT) microspheres are synthesized via a simple in situ chemical conversion route by using Fe3O4@SiO2 microspheres as a chemical template. The proposed synthesis approach is facile, low cost, and large-scale. The resulting Fe3O4@CSNT microspheres have a mean diameter of ∼300 nm, high supermagnetic cores, and a hollow copper silicate nanotube shell, which endow them with useful magnetic responsivity, good dispersibility, and stable chemical properties. Moreover, the CSNT shell of the microspheres has strong surface affinity toward contaminations. The synthesized Fe3O4@CSNT was successfully applied to convenient, efficient, and fast removal of microcystin-LR in water.