【摘要】 采用化学共沉淀法制备Fe3O4磁性纳米粒子;用柠檬酸钠进行表面修饰得到在水相中稳定分散的Fe3O4溶胶。以Fe3O4磁性纳米粒子为种子,用碱催化正硅酸四乙酯水解、缩合制备了粒径和磁性可控的核壳结构的Fe3O4@SiO2复合微球。通过FT-IR,XRD,TEM,VSM和古埃磁天平对Fe3O4@SiO2复合微球进行表征。研究了SiO2包覆对Fe3O4@SiO2复合微球性能的影响。更多还原

【Abstract】 Magnetic Fe3O4 nanoparticles were prepared by chemical coprecipitation and then were stabilized by citrate sodium,and a stable aqueous-base Fe3O4 colloid was obtained.Core-shell structural Fe3O4@SiO2 composite microspheres with adjustable diameter and magnetism were prepared by hydrolysis and condensation of tetraethyl orthosilicate using Fe3O4 nanoparticles as seeds.XRD,TEM,FT-IR,VSM and the Gouy magnetic balance were applied to characterize the Fe3O4@SiO2 composite microspheres.The effects of SiO2 coating on the performance of Fe3O4@SiO2 composite microspheres were investigated.更多还原