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This article focuses on the history of the development of the solar cell, solar cell materials, classification of solar cells, solar cell structure and working principle, nano-science and technology with solar battery, the problems of solar cells, solar battery status overview, clarifying the development of solar energy urgency. TiO 2 bandgap of 3.2eV, is a low-cost, high activity, safety, and a wide range of applications, pollution-free and stable performance semiconductor material in solar cells has been gradually by people's attention. But the energy gap is too wide, the utilization of the sunlight is too low, how to improve the TiO 2 electrode light use efficiency has been an important research topic. CdS is a bandgap of 2.42eV the Ⅱ - Ⅵ group compound semiconductor, the energy band determines the location of which can be used to good sensitized TiO 2 of the semiconductor electrode, but the CdS itself having certain toxicity. CdS particles sensitized function people had been aware of CdS nanorods, nanowires sensitized TiO 2 electrode also rarely reported. The CdS dispersed in the polymer layer, expect to overcome the toxicity problem of CdS, CdS nanorods, nanowires sensitized TiO 2 electrode and separate use as electrodes for solar cells to develop new direction of development. The content of the thesis is divided into three parts, first explored by the sol - gel method of preparing porous TiO 2 film, followed by exploration of the preparation of large area, high-purity single crystal CdS nanorods, nanowires, Finally, the first two parts together, to explore the application of the photoelectrode aspects. Porous TiO 2 film hydroxy cellulose (HPC) as additives, sol - gel prepared. In this study, first using ethanol as solvent, temperature, heat treatment time and HPC concentration system, found difficult to prepare the porous TiO ideal 2 film. Then certain solvents investigated solvents such as ethanol, ethylene glycol, ethylene glycol monomethyl ether, ethyl ether, acetone, and the glycol ether is more suitable for the preparation of the porous TiO 2 film. Finally, glycol ether as solvent, through the heat treatment time HPC concentration, layers were prepared the ideal porous TiO 2 film. Secondary heat treatment when the heat treatment temperature of 550 ° C for 60min, in the HPC concentration of 4.5mg / g solution, and plating under the conditions of 5 layers to obtain a pore size of about 80nm, Bohou about 400nm a uniform distribution of the porous TiO 2 film. CdS nanorods, nanowires, first in a small amount of modifying agent, using a chemical bath deposition method. Study by the reaction time, the the system PH value modifier content, although some yield CdS nanowires, but its system always CdS nanowires and nanoparticles coexist and nanowires Zhejiang University master's thesis polycrystalline, the results are not ideal. After the solvothermal method to prepare CdS nanowires, nanorods. Solvothermal ethylenediamine as the solvent, by the content of the modifier, and the reaction time, the reaction temperature of the system of finally obtained a large area, high purity single crystal CdS nanorods, nanowires. And the size of the nanowires better control can be obtained through the experimental conditions. In the content of the modifier in the the 0.039/50ml solvent, and the reaction temperature was 180 ° C under the conditions, the reaction time was 96h, about 7 material m, a diameter of approximately gonm uniform CdS nanowires; reaction time extended to 144h, obtained a length of about 13 to fight m, the uniformity of the diameter of about 85nm of CdS nanowires. The reaction temperature was raised to conditions of 2500C, and the reaction time for% h obtained about 20 lam m, the uniformity of the diameter of about 80nm is CdS nanowires, the aspect ratio reaches 250. The content of the modifier, and the reaction time, reaction temperature, and other experimental parameters, and the analysis of the results of the corresponding experiments, the basic analysis of the mechanism of the formation of the nanowires forming conditions. The third part of the study of porous Tio: film photoelectrode, Cds nanowires polymer film / the porous TIOZ film photoelectric polar the CdS nanowires polymer film / dense TIO: thin-film photovoltaic electrode, the the CdS nanowires polymer film photoelectrode four kinds of photoelectric pole photoelectric performance. The study found that the porous TIO: thin-film photovoltaic pole, the presence of the porous conducive to extend the light response. CdS polymer film and the TiO: film of the composite electrode, is conducive to separation of the photogenerated carriers, the light current increases and starting hysteresis weakened. Photocurrent starting hysteresis decreasing trend with increasing aspect ratio of CdS nanowires. Keywords: TIO: porous film; sol-gel method; CdS nanowires; Solvothermal; photoelectrode; photocurrent
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