热解-还原法制备单分散Fe_3O_4亚微空心球

Monodispersed Fe_3O_4 Hollow Submicro-spheres Prepared by Pyrolysis-Deoxidization

在用模板法水解FeCl3制备单分散聚(苯乙烯-共-丙烯酸)/Fe2O3[P(St-co-AA)/Fe2O3]核壳粒子的基础上,于N2环境下热解内核直接得到了单分散的磁性Fe3O4亚微空心球.用透射电镜(TEM)、场发射扫描电镜(FESEM)、X射线衍射(XRD)、振动样品磁强计(VSM)表征并测试了空心微球的结构形貌、成分以及静磁性能.结果表明,P(St-co-AA)/Fe2O3核壳粒子在热处理过程中,由于内核热解生成的有机小分子将Fe2O3壳层同时还原为Fe3O4,从而生成了粒径和壁厚均匀的单分散Fe3O4亚微空心球.该空心微球在室温下的饱和磁化强度、剩余磁化强度和矫顽力分别为50.91A·m2·kg-1、3.97A·m2·kg-1和2.33kA·m-1.

The monodispersed magnetic Fe3O4 hollow submicro-spheres were prepared by directly pyrolyzing the P （St-co-AA）/Fe2O3 core-shell particles in nitrogen, which were obtained by controlled hydrolysis of FeCl3 on the surface of template particles. The structure, composition and magnetic properties of those hollow spheres were examined by transmission electron microscopy（TEM）, field emission scanning electron microscopy（FESEM）, X-ray diffraction（XRD） and vibrating sample magnetometer（VSM） etc. The results showed that the monodispersed Fe3O4 hollow submicro-spheres with even and compact shells were produced since the Fe2O3 shells were deoxidized into Fe3O4 by the pyrolysates decomposed from the polymer cores during heat-treatment in nitrogen gas. The Fe3O4 hollow particles showed saturated magnetization of 50.91 A·m^2·kg^-1, remaining magnetization of 3.97 A·m^2·kg^-1 and coercivity of 2.33 kA·m^-1 at room temperature.