| We all know that with development of technology the environment becoming more more bad, and the scientists pay more attention on research photocatalytic materials. People would like to find a kind of material which is stable, innocuity, cheap and high photocatalytic efficiency under natural light. TiO2 just meets people’s expectations expectations. With further research it was discovered that though dioxide has a lot of good properties, but unfortunately the gap of TiO2 is 3.2eV, which led to it only absorbs ultraviolet of natural light.And when light on the surface of TiO2, holes and photogenerated electronsconform to the quickly.The both of reasons led to its photocatalytic restricted. So the scientists started from these two areas to study, find ways to improve the photocatalytic titanium dioxide in natural light. This article is also focused on these two aspects to starts experiment. We think magnetron sputtering is the best way to coat or dope,because the quality of the film is nice.The first chapter introduces the widely application of physical and chemical properties of TiO2 and TiO2 in different fields. At the same time, introduced the commonly used film preparation method and the required equipment and materials.The second chapter introduces the method of preparation of pure titanium target as well as the film, and the film characterization methods used in this experiment to the details. Finally, this paper introduces the principle of photocatalysis and concrete operation.The third chapter is the study of the band gap through C and Mo double doped titanium dioxide to change, in order to improve the photocatalytic efficiency. Using the RF magnetron sputtering method to prepare doped thin films. After all the doped samples of such as XPS, Raman, XRD, UV VIS spectrophotometer and characterized by different doping concentration (concentration of 1%,0.1%and 0.01%) on the photocatalytic properties of the films, in-depth study of the principle of doping.The fourth chapter studies is deposited on the TiO2 surface silver to form a Schottky barrier in the titanium oxide film surface, Schottky barrier can be absorbed by TiO2 electronic light is generated, which can effectively inhibit the recombination of electron hole pairs. At the same time of sputtering time of Ag (the sputtering time of 2s,5s,10s,15s) the amount of the final film structure and photocatalytic effect.The fifth chapter further detailed studies on FTO conductive glass substrate when the effect of sputtering film on titanium oxide, such as substrate temperature, sputtering power, sputtering pressure and sputtering time and substrate, by means of XRD, SEM, AFM, photocatalysis and some testing and characterization, in order to get the optimal parameters of the TiO2 thin film sputtering.The final test and calculation results tell us,with the help of C and Mo, the forbidden band of TiO2 was successfully minished and are better than the TiO2 separate function. The photocatalytic efficiency of thin film doped under visible light is indeed can be boosted, the reason is doped in thin film titanium atoms are molybdenum atoms in Mo6+ was replaced, thus forming a doping level; However, the absorption of visible light is boosted for the adsorption of carbon mainly existse on the TiO2 surface.Last we try to deposited precious metal silver on the surface of TiO2. Because when silver is sputtered on the surface of TiO2,it will take shape a schottky barrier, whiche will absorb the photoproduction electronic, thereby effectively inhibition electrons and holes. By controlling time to control the Ag sputtering deposited on the surface of titanium oxide, we set the time as:2s、5s、10s、15s. It was found that the sputtering time for 2s and 5s are samples of titanium oxide photocatalyst is helpful, and sputtering time of 10s and 15s in the sample but inhibit Photocatalytic. After that all samples were be tested such as testing and characterization XRD, SEM, AFM, and transmittance to understand the role of principle. |
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