低温液相合成纳米级软磁铁氧体材料MnFe_2O_4

Low temperature synthesis of the spinel manganese ferrite nanopar ticles MnFe_2O_4 by liquid phase

采用氧化-共沉淀相转化法低温液相合成了具有尖晶石结构的软磁铁氧体粉体材料铁酸锰。研究了非晶态δ-FeOOH的形成、反应物的加料方式、共沉淀的pH值对铁酸锰制备及性质的影响,并得到了最佳生成条件:氧化阶段二价铁离子的浓度为0.3～0.6mol/L;添加剂EDTA的浓度为0.01mol/L;Fe(OH)2悬浮液的pH值为8.7;温度18～25℃。相转化阶段共沉淀的pH值大于12.83,物料比R≥1.3。通过XRD、TEM、VSM等方法对其进行了表征。由于操作方便、设备简单、反应物成本低廉、反应条件温和且工艺条件易控,从而为大规模工业化生产提供了一条新的途径。

The spinel manganese ferrite nanoparticles were successfully prepared by oxidation-co-precipitation phase transformation at low temperature in this thesis.The effect of the formation ofδ-FeOOH,charying way of reactants and pH value of co-precipitation were investigated.The re-sults show that the optimal conditions are[Fe 2+ ]=0.3～0.6mol/L,=0.01mol/L,pH=8.7,oxidation temperature of18～25℃and pH>12.83,R≥1.3(R=2OH - /Mn 2+ )at phase transfor-mation step.Their structure characteristics and magnetism properties were studies by XRD,TEM and VSM.It is considered that the synthesis of the spinel manganese ferrite nanoparticles using this novel methods are with such outstanding characteristics as simple technological equipment ,gentle reaction conditions,low-cost raw materials,etc.It is a powerful route of industrialization.