College of Chemistry and Material Sciences, Hebei Normal University, Shijiazhuang 050024, China.
Dalton Trans. 2013 Oct 21;42(39):14261-7. doi: 10.1039/c3dt51310f.
Magnetic nanomaterials that can be easily separated and recycled due to their magnetic properties have received considerable attention in the field of water treatment. However, these nanomaterials usually tend to aggregate and alter their properties. Herein, we report an economical and environmentally friendly method for the synthesis of magnetic nanoparticles with core-shell structure. MnFe2O4 nanoparticles have been successfully coated with amorphous Mn-Co oxide shells. The synthesized MnFe2O4@Mn-Co oxide nanoparticles have highly negatively charged surface in aqueous solution over a wide pH range, thus preventing their aggregation and enhancing their performance for heavy metal cation removal. The adsorption isotherms are well fitted to a Langmuir adsorption model, and the maximal adsorption capacities of Pb(II), Cu(II) and Cd(II) on MnFe2O4@Mn-Co oxide are 481.2, 386.2 and 345.5 mg g(-1), respectively. All the metal ions can be completely removed from the mixed metal ion solutions in a short time. Desorption studies confirm that the adsorbent can be effectively regenerated and reused.
由于具有磁性而易于分离和回收的磁性纳米材料在水处理领域受到了相当大的关注。然而，这些纳米材料通常容易聚集并改变其性质。在此，我们报告了一种经济环保的方法，用于合成具有核壳结构的磁性纳米颗粒。已经成功地在 MnFe2O4 纳米颗粒表面包覆了非晶态的 Mn-Co 氧化物壳。在宽 pH 范围内，合成的 MnFe2O4@Mn-Co 氧化物纳米颗粒在水溶液中带有高度负电荷，从而防止其聚集，并增强其去除重金属阳离子的性能。吸附等温线很好地符合 Langmuir 吸附模型，MnFe2O4@Mn-Co 氧化物对 Pb(II)、Cu(II)和 Cd(II)的最大吸附容量分别为 481.2、386.2 和 345.5 mg g-1。所有金属离子都可以在短时间内从混合金属离子溶液中完全去除。解吸研究证实，该吸附剂可以有效地再生和重复使用。
