The Preparation And Properties Study Of Iron-based Compound Nanomaterials

Iron-based compound nanomaterials are a type of multifunctional materials with excellent properties and have shown broad potential applications in gas sensor, catalyst, information storage, lithium ion battery and magnetic materials. Hence, the study of the synthesis, properties and applications of iron-based compound nanomaterials has attracted more and more attention. In this thesis, we presented the synthesis of different kinds of Iron-based compound via solvothermal and hydrothermal process with the assistance of microwave and subsequent calcinations, and the properties of as-prepared products were investigated. The main achievements and innovations in this thesis are summarized as follows:1. The film composed of FePt nanoparticles coated with PVP molecules was prepared via a facile solvothermal reaction. After magnetic-field-assisted annealing treatment in the vacuum, FePt nanoparticles assemblies with decreased transition temperature and induced perpendicular orientation was obtained. In the process of magnetic annealing treatment, magnetic field induced the assemblies of FePt nanoparticles and favored the formation of ordered fct structure, which reduece the disorder-order transition temperature. At the same time, PVP molecules were transformed into carbon shells and covered on the surface of FePt nanoparticles, which not only inhibited the growth of the particles, but also reduced the exchange coupling between the neighboring particles.2.α-Fe2O3nanoparticles with various morphologies including spherical and cubic shapes were prepared via a facile solvothermal process. PVP and NH3·H2O were found to exert great influences on the morphologies of the final products. PVP was favorable to the formation of regular surface, while NH3·H2O was favorable to the formation of flat surface. Besides, the optical properties of the as-prepared products was investigated, and it was found that the morphologies of the as-prepared products can exert an impact on their Uv-vis spectrum.3. The γ-Fe2O3/grapheme composite has been successfully prepared via a facile and novel bubbling-assisted exfoliating method using grapheme oxide (GO) obtained by Hummers method and FeSO4· H2O as starting materials. The as-obtained y-Fe2O3/grapheme composite showed desirable photodegradation ability for methyl orange with excellent cycling abilities. Additionally, the products exhibited the characteristics of soft magnetism with a saturation magnetization of49.4emu/g and a coercivity of183.3Oe at room temperature. Moreover, the products can be separated easily from the aqueous solution by a magnet for reuse.