溶剂热法合成不同形貌MnFe2O4纳米颗粒及其在污水处理中的应用

通过简单溶剂热法合成表面粗糙的立方体结构MnFe₂O₄颗粒, 样品粒径约为150 nm, 立方体表面球状突起的直径约为10 nm, 该特征增加了样品的比表面积。反应过程中, 通过改变表面活性剂CTAB的加入量, 有效影响晶体各个晶面方向的生长速度, 最终合成不同形貌的样品(立方体、多面体、正八面体结构)。合成样品在室温下都表现出典型的铁磁性质。通过对刚果红和重金属离子Cr^VI和Pb^II溶液的吸附实验证明, 表面粗糙的立方体结构MnFe₂O₄颗粒在污水处理过程中, 可以更高效地去除水中的污染物, 通过磁分离技术回收样品以便再利用, 提高废水净化率。

Synthesis and Characterization of MnFe2O4 with Different Morphologies and Their Application in Water Treatment

Manganese ferrite (MnFe₂O₄) with rough surface was synthesized by a simple solvothermal method. The average diameter of particles was about 150 nm, and the tubes of rough surface about 10 nm. Here, magnetic MnFe₂O₄ particles with different morphologies (cube, polyhedron and octahedron) were successfully prepared by controlling CTAB concentration. Both of the samples with different morphologies exhibit ferromagnetic behavior at room temperature. The saturation magnetization (M_s) and coercivity (H_c) of MnFe₂O₄ with non-smooth surface are 58.7 Am²/kg and 6.23 kA/m, respectively. The particles with rough surface also show good performance in removal of pollutants like Congo red (92.4 mg/g), Cr^VI (54.4 mg/g), and Pb^II (84.4 mg/g) from waste water by adsorption experiments. Because the particles are recollected by magnetic separation, the waste water purification rate can be improved, which expands the applications of magnetic materials.