Hierarchical core–shell structured Fe3O4@NiSiO3 magnetic microspheres: preparation, characterization, and adsorption of methylene blue from aqueous solution

Core–shell structured Fe₃O₄@NiSiO₃ magnetic microspheres are synthesised and possess high porosity and magnetic properties, which allow the microspheres to exhibit efficient adsorption of methylene blue and convenient separation from wastewater.