Synthesis of Water-Soluble Fe3O4 Nanop

In this work, water-soluble Fe3O4 nanopowder with mesoporous structure was prepared by the thermal decomposition of Fe-urea complex ([Fe(NH2CONH2)(6)](NO3)(3)) in triethylene glycol (TEG), and the effects of reflux time and the concentration of precursor on the properties of Fe3O4 nanopowder were investigated. In addition, the adsorptive properties of the material were studied using Cr(VI) as a target pollutant. Prolonging reflux time and increase in concentration of [Fe(NH2CONH2)(6)](NO3)(3) in TEG can effectively improve the crystallinity and magnetic properties of the Fe3O4 nanopowder. The saturation magnetization (Ms) increases from 21.4 to 48.5 emu/g when the reflux time increases from 2 to 20 h. The maximum adsorption capacity of the Fe3O4 nanopowder for Cr(VI) is estimated to be 21.6 mg/g.