Nano Materials Prepared By Thermal Decomposition

The physical and chemical properties of materials are closely related to their size and shape. Monodispersed nanomaterials have caused great attention in recent years. Among various preparation techniques of monodispersed nanoparticles, thermal decomposition has been developed rapidly. Here we used this method to synthesis two different kinds of material in this paper.As a kind of wide band-gap semiconductor, nano-structured ZnO show novel properties, which makes ZnO to be thea kind of promising material, which is widely used in photoelectric devise, catalysis, rubber, ceramic and make-up industry. With the increasing concern on the preparation process and properties of ZnO with different size and shape, combined with the faster development on it's applications in various field, monodispered ZnO nanomaterial has received more and more intensive interests. Zinc ferrite, ZnFe₂O₄, is a kind of antiferromagnetic spinel ferrite and have antiferromagnetism. When the particle size decreases into nano scale, the particles would own some unusual magnetic properties, rendering broad application of zinc ferrite in electronics, information, communication, military, and so on. Hence, the preparation propertly and structure of zinc ferrite have become the research focus throughout the world.In this paper, we introduce the development of nano materials development, which followed by basic features of ZnO and Zinc ferrite. With the help X ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron micropy (HR-TEM), scanning electron microscopy (SEM), photoluminescence (PL), and some measurement such as hyseresis, field-cooling and zero-field cooling (FC-ZFC), relaxation and the fitting theoretically for zinc ferrite, can we check the properties and analyses the mechanism of the material, the out-coming are as follows:(1) We get ZnO particles with different shapes through thermal decomposition method. Besides, we analyse some parameters such as time, temperature andsurfactant which have great impact on the result.(2) We get zinc ferrite nanoparticles via thermal decomposition in the high boil-point solvant from zinc acetate Zn(Ac)₂·2H₂O and ironpentacarbonyl Fe(CO)₅. High magnetization can be obtained from the hysteresis measurement, indicating the ferrimagnetism of zinc ferrite.(3) By ZFC curve fitting on real size distribution which obtained from TEM, we have analysed the origin of the magnetization and the mechanism and got the conclusion that the magnetization derive from A-B superchange interaction which produced by Fe ions displacement and surface spin canting.