| Nano-materials are considered as the most promising materials in 21st century. It is a major discovery in the history of modern science. When the size of the materials reduced to the nano dimension, it will have some expecially property compared to the bulk materials. It has become the and research focus in the field of materials science. Due to the unique property of the semiconductor materials, they have been widely applied in many fields. Among these semiconductor materials, ZnO has been used in many aspects. Zinc oxide, with a direct wide band gap of 3.37 eV and large excitation binding energy of 60 meV at room temperature, is one of the most important functional materials, which has potential applications in catalyst, sensor, electronic, optical, optoelectronic and piezoelectric devices, etc.ZnO, which will be used in catalysis, as the photocatalytic degradation of organic pollutants has been used more and more widely. There are several ways that we can improve the photocatalytic properties of ZnO:reduce the size of semiconductor particles, the semiconductor compound between the surface sensitization, metal ion doping and deposition of noble metal.In this paper, we used metal ion doping and deposition of noble metal to improve the photocatalytic of ZnO. There is no obvious conclusion in the influence of photocatalytic efficiency which is induced by the doing ions. Another method to improve the photocatalytic efficiency is to disperse metal such as Ag, Au, Pt in ZnO nanocrystals. This is sure. Almost all the literatures have reported that in the appropriate ratio the silver has stimulative influence on the photocatalytic efficiency. So we can modify Ag onto ZnO samples to research the ZnO photocatalytic efficiency and the mechanism of the doping ions in the efficiency of the photocatalytic. In our report we research (i) the doping ions in the influence of the photocatalytic efficiency, (ii) modifying Ag onto doped ZnO and its improve photocatalytic activity which has rarely reported.Hydrothermal method applied to the preparation of crystalline integrity, smaller particle size powder product. The products by this method have high purity, less conglomeration, and narrow particle size distribution. This paper use simple hydrothermal method, in different systems which contains benzyl alcohol,glycol,ethanol. We have prepared doped ZnO materials which is in micro and nano dimensions. And then we research its character.The main content of this thesis include the following two parts:(1) In this synthesis, the Zn1-xOMx micro/nanostructures with controllable morphology were successfully synthesized by hydrothermal process. The XRD,SEM,TEM,HRTEM were used to characterize the structure and morphology of the as-obtained samples. We have also investigated the growth conditions such as solvent, alkali ratio, temperature, and reaction time in the morphology of the samples. And we also research the possible growth mechanism responsible for the variation of the structures(2) We have adopted the simple hydrothermal method and use the ethanol as the solvent to synthesis Zn1-xFexO (x=0,0.01,0.02,0.04) samples in different doped ratio. The XRD,EDAX,TEM,HRTEM were used to characterize the structure and morphology of the as-obtained samples. The prepared samples are 20nm nanoparticles. UV-Vis absorption spectra were used to detect the structure and properties of the as-prepared samples. We used the prepared Zn1-xFexO samples to research the doped ions and Ag in the influence of photocatalitic efficiency. Finally, we got some reasonable explanation and meaningful results. |
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