| TiO2 is an important inorganic functional materials.Because of its humidity, gas, photoelectric conversion, dielectric effects, photochromic and excellent photocatalytic performance. TiO2 has a wide range of application in many fields such as sensor, dielectric materials, optical materials, self-cleaning materials, catalysts and carriers and so on.TiO2 nanotubes are another form of TiO2 materials. As nanotubes with a large surface area and has a high adsorption capacity, is expected to enhance the photocatalytic properties of TiO2, especially if a smaller inorganic, organic, metallic or magnetic nanoparticles assembled into TiO2 nanotubes, to assemble composite nanomaterials. It will greatly improve the photovoltaic, electromagnetic and catalytic properties of TiO2.Titanium dioxide exist two main shortcomings that is low solar energy utilization, photo-electronic and photo-generated hole can easily composite. The two main shortcomings greatly limits the practical application of TiO2 due to its low photocatalytic efficiency. Zinc oxide is a direct band-gap semiconductors, titanium dioxide is the indirect band-gap semiconductors. The band gap between the two materials is very close. Energy from the end of the conduction band to the top of valence band is very similar. To couple the two can have a major impact on their optical properties.Studies have shown that the introduction of zinc oxide can inhibit the process of crystalline transformation of titanium dioxide and particle growth. As a result ZnO-TiO2 semiconductor showed higher photocatalysis efficiency compared with single ZnO and TiO2 under ultraviolet, natural light and sunlight. What's more the absorption spectrum red shift occurs.This paper mainly studies the preparation and related properties of ZnO nanorods, TiO2 nanotubes, TiO2/ZnO nano-composites. In this paper we provide theoretical basis and experimental foundation for the nano-materials above-mentioned to expand more extensive applications. Details are as follows:(1) ZnO nanorods with different morphologies are obtained with different raw materials and reaction conditions. These ZnO nanorods have hexagonal wurtzite crystal structure, dispersed uniform and obvious agglomeration unobserved.Discussed the effect of raw materials composition, reaction temperature, reaction time, alcohol-water ratio, surfactant on the formation of ZnO. Preliminary analyze the formation mechanism of ZnO. ZnO crystallite obtained the best morphology With 0.04M of Zn(NO3)·6H2O, and 0.05M of (NH4) 2CO3, used SDS as assisted surfactant, at 2:1 volume ratio of alcohol/water system, at 200℃hydrothermal reaction 10 hours. The ZnO nanorods with an average diameter of about 59nm and aspect ratio up to 40. We make use of XRD to identify obtained ZnO crystallite with a hexagonal wurtzite structure, small size, well crystalline, and the results are in accordance with TEM.(2)Electrochemical anodic oxidation method is adopted. In the presence of F-, TiO2 nanotubes with orderly, tightly arranged hollow tubes are obtained.By adjusting the process of preparation conditions, we can see the TiO2 nanotubes are influenced by anodization voltage, reaction time, pH value. We optimized The technology on the preparation of TiO2 nanotubes. We obtained the best anode voltage of 60V, pH value of 6, and reaction time of 9 hours. The results from SEM analysis we observed the average diameter of TiO2 nanotubes are about 100nm with a high aspect ratio. Confirmed by XRD analysis we identified the crystalline structure of TiO2 nanotubes.They have well crystalline structure and the results are consistent with the SEM.(3) Using a two-step method successfully prepared TiO2/ZnO nano-composite with regular and clear core- shell structure. Using EDS analysis to certificate the elemental composition ofthecomposites, which are made up of titanium, zinc, and oxygen.Experiments prove that the surfactant, zinc content have great impact on morphology of TiO2/ZnO nanocomposite. Surfactant affects the size of zinc oxide in nanocomposite materials, which may be caused by the polarity of surfactant. Using SDS as surfactant can get nearly a half smaller size than CTAB. Zinc content concluded in nanocomposites has effect on surface morphology of composite. We obtained the best morphology of TiO2/ZnO nanocomposites when the zinc content in the composites is up to 0.00002M. Too much zinc conten will block titanium tubes and cover titanium tube-shaped holes.TiO2/ZnO nano-composite materials formed on the basis of the formation of TiO2 nanotubes. By heterogeneous nucleation, TiO2/ZnO nanocomposites formed.(4) Using methyl orange as the goal of degradation, natural light as the light source to study the activity of TiO2/ZnO nano-photocatalytic. Results showed that, TiO2/ZnO composite photocatalyst can improve the utilization of the sunlight. It is found that the best degradation of catalytic is observed to reach 90% when the solution pH value equals 3, in sunlight degradation 5 hours.
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