Integration of hierarchical magnesium silicate with polypyrrole-coated hollow Fe3O4 hybrids as a synergistic adsorbent toward efficient water treatment

Here we demonstrate the rational design and synthesis of hierarchical Fe3O4@PPy/Mgsilicate composites for applications in water treatments. Through a facile step-by-step strategy, ultrathin Mgsilicate nanosheets (NSs) are grown on polypyrrole (PPy) coated Fe3O4 NPs to achieve the hollow structured Fe3O4@PPy/Mgsilicate composites. This smart design can effectively shorten the mass transfer of molecules, increase the specific surface area, and provide more active sites for adsorption of organic pollutants. Owing to its large specific surface area, hierarchical hollow structures, and the synergistic adsorption effect between the PPy interlayer and magnesium silicate outlayer, the resulting composites exhibited excellent adsorption on Congo Red (CR) with high adsorption capacity of 540.5 mg·g-1. The separation of the composites after sorption can be easily performed with an external magnet because of the multiple Fe3O4 cores. These results indicate that the Fe3O4@PPy/Mgsilicate composites can be employed as a highly promising adsorbent in water treatment.