| Nano-materials, especially of nano-particles, because of their unique properties: Small size effect, Quantum Hall effect, etc., have been the focus of scientific research materials. Barium titanate (BaTiO3) nano-powders, with outstanding electrical properties such as high dielectric constant, ferroelectric, piezoelectric, and positive temperature coefficient effect, are widely used in electronic ceramic industry. Firstly, by using the cheap industrial-grade metatitanic acid as the raw materials, we obtained a good dispersion of barium titanate powders by hydrothermal reaction. Subsequently, we analyzed the influence of process conditions on the structure of the product and morphology, such as the hydrothermal reaction temperature and time, the ratio of barium and titanium, and finally determined the optimum conditions.Nano-thin film is also a hot investigation in the field of materials science. Niobium oxide film has excellent optical property. It is a dielectric material with high band gap and strong ultraviolet absorption capability, and the refractive index is also high. Therefore, they are widely used in the fields of optical applications. At beginning of our work, we synthesized the inorganic layered compound of K4Nb6O17, through protonation and the intercalation of TBAOH, the spacing of the layered compound was expanded. Then we got the niobium oxide nano-sheets suspensions by mixing stripping. Making the stable dispersed nano-sheets suspensions as the raw material, we prepared the PEI/niobium oxide thin films through layer by layer method. Using XRD, SEM, TEM and other structural analysis methods, we studied the morphology, micro-structure; Meanwhile, Their optical properties were measured by UV-visible spectrophotometer. The studies proved that the Niobium oxide optical thin films prepared by LBL method can keep amorphous structures even if at 800℃, and the surface of the films was smooth, it has a high adhesion,high refractive index and low extinction coefficient. From the UV-visible transmission spectrum, we can see that they also have a high rate of perspective, and are good performance of the nano-sheets optical films.Graphene is another special two dimensional nanostructures material. The remarkable properties of graphene reported so far include high values of its Young's modulus, fracture strength, thermal conductivity, mobility of charge carriers and specific surface area, plus fascinating transport phenomena such as the quantum Hall effect. It attracted much attention from the scientists in the basis research and technology applications. Grinding graphite and other Lewis acids as the starting regents by our new screw grinding machine, and then treated them with hydrochloric acid and potassium hydroxide respectively, finally we obtained good water-soluble graphene suspensions. Afterwards, we use the grapheme suspensions as the raw materials, and get the film through LBL methods, with the feature of uniform thickness, smooth surface and high adhesion. Finally, we measured the response of the film resistance according to temperature and pressure, preliminary studied the possibilities about this materials' application in the temperature and pressure sensors and so on.
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