文档介绍：Fe304纳米颗粒及Si02/、结晶度高并且具有高饱和磁化强度,自组装结构四氧化三铁纳米颗粒的溶剂热法合成以及磁性二氧化硅复合纳米颗粒的制备。采用一步溶剂热还原法,以乙二醇作为溶剂和还原剂、三氯化铁提供铁源、醋酸钠作为稳定剂、油酸钠作为表面活性剂,反应温度为200℃制备出了具有自组装结构的四氧化三铁纳米颗粒。利用X射线衍射(XRD)、拉曼光谱、XPS对产物进行物相表征,采用透射电镜(TEM)和扫描电镜(SEM)对产物的粒径大小和形貌进行分析。分析结果表明:产物四氧化三铁为反尖晶石结构,结晶度好,颗粒呈现类似于石榴的自组装结构,粒径大小均匀,没有明显团聚现象。 emu/g,显示出极好的磁响应性。研究了主要反应条件对实验结果的影响。结果表明:反应温度、反应时间及反应物对产物的粒径大小及形貌均有显著影响。以溶剂热法合成的四氧化三铁纳米颗粒作为生长基,在同样反应条件下二次溶剂热反应后制备得到了表面光滑的四氧化三铁微球。采用XRD和SEM对产物进行表征后,结果发现所得四氧化三铁颗粒表面光滑,粒径为l lam左右,分散性好。讨论了四氧化三铁微球可能的形成过程。分别利用溶剂热法和共沉淀法合成的四氧化三铁颗粒作为种子,采用液相沉积法将TEOS直接分解并沉积在Fe304纳米颗粒种子表面,制备得到形貌完整,粒径均匀,磁性可控的球形Si02/Fe304复合纳米颗粒。讨论了TEOS用量对二氧化硅磁性复合颗粒的形貌和磁性能影响以及Si02在Fe304纳米颗粒种子表面沉积的机理。关键词:四氧化三铁,磁性材料,溶剂热合成,二氧化硅作者:张玮指导老师:沈风雷副教授 Synthesis of ic Fe304 microparticles and Si02/posite sp heres Abstract ite particles exhibitsome individualproperties because oftheir unique physical and chemical properties,and have a wide range of potential applications in such areas ic recording,ferrofluids,catalytic carrier, biomedicine and pollution focused on thesynthesis of ic Fe304 microparticles viaself-assembly ofFe304 nanoparticles which have many excellent properties including monodisperse,well crystallization,higher ization,as well asthepreparation ic Si02/posite spheres.‘ ic Fe304nanoparticles were synthesized andthen self-assembled into microparticles via asolvothermal method,using FeCl3’6H20 as theironsource,sodium oleate as thesurfactant,and ethylene glycol as thereducing agent obtained Fe304 microparticles were characterized byX-ray powder diffraction(XRD), spectroscopy(xPs),Raman spectroscopy and Vibrating sample ometer(VSM).The sizeandmorphology oftheparticles wereexamined using Transmission electron microscopy(TEM)and Scanning electron microscopy(SEM). The Fe304 microparticles ofnearlymonodisperse diameters,controllable intherange of 20-400 nm,consist ofassemblies ofFe304nanoparticles谢th adiameter of 22 nln. The e