Structure and characteristics of superparamagnetic Fe_3O_4 nanoparticles by three synthesis methods
LI Tian-qi;SUN Ning;HU Fei;School of Light Industry and Food Science, South China University of Technology;
Superparamagnetic Fe3O4 nanopar ticles were prepared by chemical co-precipitation, hydrothermal synthesisand sonochemistry. Morphology, magnetization and other properties of particles were studied and compared by TEM, IR, XRD, PPMS. The precipitated precursor of Fe3O4 nanoparticles was made under the condition of n(Fe3+)/n(Fe2+) as 1.6, p H value as 9, ammonia as precipitant. The result showed that the optimum condition of above three methods, the prepared Fe3O4 nanoparticles were monodispersed quasi-spherical nanoparticles with average diameter of about 8.49, 9.75, 8.79 nm, respectively, of which the saturation magnetization were 60.9, 67.5, 65.4 emu/g, respectively. In the meanwhile, Fe3O4 nano-particles prepared by hydrothermal synthesis had higher saturation magnetization and Fe3O4 nano-particles prepared by chemical co-precipitation had better dispersion property and crystal structure. Furthermore, as high activity hydroxyl groups of nano-particles' surface was conducive to surface and functional groups modification, the superparamagnetic Fe3O4 nano-particles could be widely used in immobilized enzyme' carriersand etc.
【CateGory Index】： Q814.2;TQ138.11