微波加热对锰锌铁氧体纳米粉体制备的影响

Effects of microwave heating on preparation of Mn-Zn ferrite nanoparticles

采用硫酸亚铁、硝酸铁和氢氧化钠为原料，通过微波加热方式与共沉淀法结合制备了四氧化三铁纳米粉体。通过XRD、激光粒度分析和SEM对所得粉体进行了研究，同时研究了表面活性剂加入方式对粉体的影响。结果表明，微波加热可促进四氧化三铁纳米粒子的晶化，在30min加热时间内，可制得平均粒径为13～16nm的四氧化三铁纳米晶粒。通过对微波加热功率和时间的控制，可实现晶粒的可控生长。采用聚乙二醇作为表面活性剂，可明显减弱粉体的团聚现象，在微波辐照前加入活性剂的方式优于在微波辐照后加入活性剂的方式。采用微波加热可以极大地促进粉体的晶化，有利于纳米晶的迅速形成，对于合成纳米晶具有潜在的优势。

Using FeSO4, Fe（ NO3 ）3 and NaOH as raw materials, Fe3O4 nanoparticles were prepared by combining co - precipitation method with microwave heating. The synthesized nanoparticles were investigated by XRD, Laser Particle Sizer and SEM. Meanwhile, the effect of additional way of surfactant on the nanoparticles was researched as well. Results indicated microwave heating can promote the crystallization of Fe3O4 nanoparticles and the Fe3O4 nanoparticles with average crystalline size about 13 - 16 nm were prepared in 30 min of microwave heating. Through controlling on the power and duration time of microwave, the crystal growth become controllable. The agglomeration phenomenon of nanoparticles apparently reduced while using PEG as surfactant. It is better to add the surfactant before the reaction than to add it after the reaction. Results also revealed that microwave heating can accelerate the crystallization of nanoparticles;it is favorable for the quick formation of nanocrystal and has potential advantages of synthesizing nanocrystal.