| Nanomaterials have aroused tremendous interest in physics and other subject due to their unique properties, such as the large surface area, the performance of the material can be directly affected by the performance of the interface state atoms and then variety of new physical and chemical properties can be introduced in the nanomaterials. The synthesis and the research of their properties of the nanomaterials is an important frontier in physics research area.The main contents of this paper can be shown by three parts as follows:1. The synthesis of the AAO templateMany methods can by used to synthesize nanomaterials. The nanomaterials synthesized by template growth method possess the controllable stable size and low-cost characteristics. In particular, the Anodic Aluminum Oxide (AAO) template have many advantages, such as having high hole density, orderly arrangement, uniform distribution, controllable hole size, heat resisting, good thermostability, high mechanical performance, high hardness, canAAO template was prepared by anodic oxidation method. The influence of the oxidation times, reaction time and other factors on the degree of order, diameter, wall thickness, etc. of the template were explored. SEM images show that the holes of prepared AAO template are orderly, and almost have a same pore size and a same morphology. The results of XRD analysis show that the AAO film prepared are composite by amorphous alumina, and the unoxidized aluminum film does not exist in the AAO film. By increasing the times of oxidation, the hole of the AAO templates also can be expanded. The template made by the repeatedly oxidation have more uniform hole diameters than those made by expanding the hole directly. At the same time, very few bad holes can be seen in the the template made by the repeatedly oxidation. CdS nanowires were prepared on the AAO template made by three times oxidation, and the diameter which are about 70 nm. The results show that the nanowires can be synthesized effectively by AAO template.2. The prepareration and property study of Fe3O4 nano-particlesFerroferric oxide (Fe3O4) is a naturally ferromagnetic material with high coercivity. When the scale of the Fe3O4 is reduced, it can also maintain good magnetic properties. Due to the quantum effect, and the surface effect, Fe3O4 show many unique properties that the massive magnetic materials do not exist such as the high coercive force, and superparamagnetic properties.FeCb · 6H2O was used as raw materials, ethylene glycol was used as solvent and reducing agent, the Fe3O4 nanoparticles were prepared by hydrothermal method. The XRD data fitted with MDI-Jade show that the Fe3O4 is uniform with a average grain size of about 20nm. VSM studies show that this sample was semi-ferrimagnetic. The influences of reaction time and temperature on the morphology were also studied. XRD indicated that when the Fe3O4 was synthesized at 190? and the reaction time is 18 h, the attained particles have minimum grain size with well crystallized and without impurity phase.3. The prepareration and property study of Fe3O4 CdS compositeFe3O4 nanoparticles were used as the core covered by CdS to form hybrid structure. Synthesized Fe3O4-CdS nanomaterial is magnetic and fluorescent inwardness. TEM images of the particles have different interior and exterior contrast. XRD measurements indicated that only the Fe3O4 and CdS diffraction peaks present in data. Therefore the synthetic materials are the CdS coated Fe3O4 nanomaterials. The samples at room temperature exhibits magnetization of 7.33 emu/g. The fluorescent emission peak of the sample is 360nm. There is no emission peak of the Fe3O4 fluorescent spectrum. The data of VSM and fluorescent spectra of synthetic material also proved to CdS coated Fe3O4 nanoparticles. |
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