Sea-urchin-like iron oxide nanostructures for water treatment

Abstract

To obtain adsorbents with high capacities for removing heavy metals and organic pollutants capable of quick magnetic separation, we fabricated unique sea-urchin-like magnetic iron oxide (mixed γ-Fe2O3/Fe3O4 phase) nanostructures (called u-MFN) with large surface areas (94.1m2g−1) and strong magnetic properties (57.9emug−1) using a simple growth process and investigated their potential applications in water treatment. The u-MFN had excellent removal capabilities for the heavy metals As(V) (39.6mgg−1) and Cr(VI) (35.0mgg−1) and the organic pollutant Congo red (109.2mgg−1). The u-MFN also displays excellent adsorption of Congo red after recycling. Because of its high adsorption capacity, fast adsorption rate, and quick magnetic separation from treated water, the u-MFN developed in the present study is expected to be an efficient magnetic adsorbent for heavy metals and organic pollutants in aqueous solutions.