多元醇还原法制备Fe3O4纳米粒子及磁性能表征

Preparation and magnetic property of Fe_3O_4 nanoparticles by polyol reduction method

采用简便的多元醇还原法合成Fe3O4磁性纳米颗粒,研究了稳定剂类型、初始反应温度、初始反应时间和熟化时间对Fe3O4纳米颗粒形貌、粒径及磁性能的影响。采用XRD、TEM、SQUID多种表征手段对Fe3O4纳米颗粒进行表征,结果表明:聚乙二醇作为稳定剂制备的Fe3O4纳米具有高结晶度以及单分散性,在300K下,具有超顺磁性和较高的饱和磁化强度;十二烷基磺酸钠和十六烷基溴化铵作为稳定剂却无法得到Fe3O4。稳定剂油酸/油胺的摩尔浓度比为1∶1时,升高初始反应温度从125℃到200℃,对Fe3O4的粒径和磁性能有决定性的影响;延长初始反应时间和熟化时间有利于提高纳米颗粒的分散性。

Fe3O4 nanoparticles were synthesized though polyol reduction method, the effects of stabilizer, initial reaction temperature, initial reaction time and ageing time on the morphology, size and magnetic properties of Fe3O4 nanoparticles were researched. The Fe3O4 nanoparticles were characterized by XRD, TEM and SQUID. The results shown that Fe3O4 nanoparticles prepared by PEG 4000 had high crystallinity and showed superparamagnetic behavior at 300 K with higher saturate magnetization. However, it could not be synthesized by using sodium alkyl sulfonate and cetyhrimethylammonium bromide as stabilizer. When the mol concentration ratio of oleic acid to oleylamine was 1 ： 1, increasing the initial reaction temperature from 125℃ to 200℃ which had crucial effect on the size and magnetic properties of Fe3O4 , at the same time, the dispersibility of nanoparticles increased with increasing initial reaction time and ageing time.