一步法制备针状Fe_3O_4

One-step preparation of acicular magnetite

在磁场诱导下一步制备针状Fe3O4,考察了影响产品成分的主要因素,得到了最佳工艺条件。探讨了磁场对Fe3O4生长过程的影响,结果表明,磁场对粒子形貌影响显著,随着磁场强度增大,粒子由球形转变为针形,且产品中针形粒子比率增加;在0.35T磁场下,Fe3O4形貌变化过程为:絮状→六方片状→米粒状→针状。

One-step method was adopted to prepare acicular magnetite under magnetic field. The major influencing factors on the composition of the product were investigated. The optimum process conditions were obtained. The influences of magnetic field on growth of particles were discussed. The results indicate that magnetic field has remarkable effect on the shape of magnetite. Magnetite particles change from spherical into acicular shape with the increasing of magnetic field strength. The higher the magnetic field strength is, the more acicular particles the product has. Under 0.35T magnetic field, shape transformation process of precipitate is from flocculent to hexagonal, then to granular, and finally to acicular particles.