Fe_3O_4/MnO_2磁性复合颗粒的制备及表征

Characterization and Preparation of Fe_3O_4/MnO_2 Composite Magnetic Particles

以纳米Fe3O4颗粒为核,分别采用液相沉积法和溶胶-凝胶法两种方法将MnO2包覆在其上制备了Fe3O4/MnO2磁性复合颗粒,并借助XRD、TEM、FTIR和VSM等手段分别对纳米Fe3O4颗粒和两种复合颗粒进行表征。结果表明:采用液相沉积法进行包覆可生成以多个纳米Fe3O4颗粒为核、粒径约为200 nm的近球形Fe3O4/MnO2磁性复合颗粒,其饱和磁化强度为24.4 kA.m-1;采用溶胶-凝胶法进行包覆则生成以单个纳米Fe3O4颗粒为核、粒径约为50 nm的磁性复合颗粒,包覆层为絮状MnO2,其饱和磁化强度为16.5 kA.m-1。

Using nano-Fe3O4 particles as cores, Fe3O4/MnO2 composite particles that MnO2 coating on the cores were prepared by fluid deposition method and sol-gel method. The structure and morphology of the nano- Fe3O4 particle and composite particles were characterized by the means of XRD, TEM, FTIR and VSM. The results indicate that the size of Fe3O44 / MnO2 composite particles prepared by fluid deposition method and contained several Fe3O4 particles as core was about 200 nm, and the size of the composite particles prepared by sol-gel method was about 50 nm The saturated magnetizations of Fe3O4/MnO2 composite particles were 24. 7 kA · m^-1 and 16. 5 kA · m^-1 respectively.