Tunable Synthesis Of Magnetic Nanoparticles And The Related Structures

The research background of this paper is based on the preparation of magnetic materials for tumour therapy by magnetic fluid hyperthermia(MFH).The materials in this application are required to be biocompatible, of which the Fe3O4 with low biotoxicity are rational candidates. At the same time, the heating ability of the iron oxide nanoparticles is due to the synthesis route and is directly related with the efficiency of the therapy . So a tunable synthesis route of related iron oxide nanoparticles is necessary. Further, a research of the tunable synthesis and the development of related iron oxide nanoparticles are of importance to the research of MFH therapy.Firstly,we have prepared magnetite nanoparticles by sol-gel method. And in this paper, we will talk about the influence of the different original concentration of the solution on the production. We found that using this method we could prepare the magnetite nanoparticles with different diameters from 40nm to 1200nm . The obtained samples were characterized by Transmission Electron Microscopy (TEM) and X-Ray Powder Diffraction (XRD) in structure and appearance, and by Vibrating Sample Magnetmeter(VSM) in magnetism. These data show that we can use this method to fabricate the particles which are cubic spinel geometry; orbicular, symmetrical in size, and they have different diameters; the appearance and magnetism of them are different with each other.Secondly,one-dimensional magnetite chains of spheres with different radii and lengths were prepared by aging ferrous hydroxide gel with KNO3 under different external magnetic fields which induced the ultra-fine magnetite particles to combine into chain structure. The magnetite particle size,morphology and the chain length could be adjusted by varying the field intensity. The hysteresis loops were measured in different directions The result show that the ordered 1D pattern behaves a uniaxial anisotropy originating from the effects of shape anisotropy and the multi-domain of the each Fe3O4 particle.Finally, when preparing the magnetite nanoparticles ,we add the L-Glu in the solution .By this method, we can get the hollow microspheres of Fe3O4 . In addition, we can also get the one-diamension structure materials of Fe3O4 hollow microspheres under different external magnetic fields which can induce the hollow microspheres to combine into chain structure. The abtained samples were characterized by TEM,SEM,XRD,IR and VSM.And by analysing its morphology and magnetic characteristic ,we can study its growth mechanism better.