Fe3O4磁性纳米粒子的共沉淀法制备研究

Study on preparation of magnetic Fe_3O_4 nano-particles with liquid-state co-precipitation method

叙述了以液相共沉淀法制备纳米磁性Fe3O4粒子的工艺,研究了反应搅拌速度、n(Fe3+)/n(Fe2+)的比例、pH值和熟化温度对制备纳米Fe3O4粒子的影响,并利用透射电镜表征观察Fe3O4纳米粒子的形貌。研究结果表明,在搅拌速度较快的情况下制备纳米级Fe3O4颗粒的最佳合成工艺条件为:n(Fe3+)/n(Fe2+)为1.8∶1(摩尔比),熟化温度70℃,熟化时间30 min,以氨水作沉淀剂最佳pH值是9左右,可制得纯度较高,粒径小于10 nmFe3O4磁性粒子。

The process of liquid-state co-precipitation method was studied in preparing nanometer magnetic Fe3O4. The effect of the stirring speed, the ratio of Fe^3＋/Fe^2＋ on the grain size, pH and the curing temperature on the preparing of magnetic Fe3O4 nano-particles were investigated. The morphology of Fe3O4 nanoparticles were studied with TEM. The result showed that the optimum technical process conditions are as follows：n（ Fe^3＋ ）/n（ Fe^2＋ ） is 1.8, the reaction temperature is 70 ℃, the reaction time is 30 min,pH is about 9 in the presence of ammonia as precipitant, under this condition the product is prepared successfully,which purity is higher, average grain size is less than 10 nm.