| In the thesis, the materials, the principle and structure of different kinds of the solar cells, the relation between nano-science and the solar cells, the development of the solar cells and the problems in the solar cells were reviewed. It is illuminated that the urgency of the exploitation of the solar energy. As an important semiconducting oxide, TiO2 has been extensively investigated in the field of solar cells. While the band gap of it is too broad to absorb the solar radialization effectively. II -VI semiconductor CdS has been found to expand the range of light absorption in TiO2-base solar cells early with the band gap is 2.42eV, but it has the toxicity itself. In this thesis, CdS will disperse in polymer, then use in TiO2-base solar cells which can resolve the toxicity of the CdS in a certain extent. Moreover, we offer an news idea that apply the CdS nanowires in solar cells photoelectrode.This thesis consists of three parts, those are synthesis of porous TiO2 thin films, synthesis of large-scale single-Crystal CdS nanowires with high purity and the application of porous TiO2 thin films and single-Crystal CdS nanowires in the solar cells as the electrolyte.First part, we synthesized the porous TiO2 films via sol-gel method with the hydroxypropylcellulose (HPC) as additive. We used the ethanol as solvent at first, but we had not obtained the porous TiO2 films though the change of the experiment parameters such as varied concentrations of HPC, reaction temperature and the heat treatment time. Then we put the light on the solvents. Glycol, ethylene glycol monomethyl ether, aether, acetone including ethanol were investigated. It is found that ethylene glycol monomethyl ether is more suitable solvent than others. Finally, we synthesized the mesoporous titania films with large pore size and high density of pore, narrow pore-size distribution using ethylene glycol monomethyl ether as solvent with varied the experiment parameters. The typical porous TiO2 films have an uniformity pore with pore size about 80nm, thickness about 400nm synthesized at concentrations of HPC is of 4.5mg/g solution, the heat treatment time is of 60min at 550℃.The second part of this thesis is the synthesis of large-scale single-Crystal CdS nanowires with high purity. Two methods were adopted to prepare the CdS nanowires. Firstly, we prepare the CdS nanowires via chemical bath deposition method with some additive. We obtained the CdS nanowires via exploration the experiment parameters of PH, reaction time and the concentrations of additive. But the purity and yield is not reaching the point we wanted. After analysis the problems in this method, we then synthesis the CdS nanowires via solvothermal route with ethylenediamine as solvent. The experiments parameters including temperature, reaction time and the concentrations of additive were pursued. We obtained a wonderful resolute finally. We synthesis the large-scale single-Crystal CdS nanowires with high purity and the size of the nanowires are also uniform. The typical CdS was synthesized at 250 ℃, reaction 96h and 0.03g DPTA/50ml solution, with the length about 20 μ m and the diameter about 80nm. Moreover the optical properties of the samples were investigated, UV-vis absorption spectra indicates that CdS nanowires have it's unique optical properties.The third part of this thesis is the application of the porous TiO2 films and the single-Crystal CdS nanowires in the electrode. Four sorts electrodes were investigated, porous TiO2 films electrode, CdS nanowires polymer layer/ porous TiO2 films electrode, CdS nanowires polymer layer/ non-porous TiO2 films electrode and CdS nanowires polymer layer electrode. CdS nanowires polymer layer is made by CdS nanowire dispersed homogeneously in polymer layer. It is found that porous TiO2 films can expand photoresponse range and the CdS nanowires favor for reducing the time for photocurrent arise.
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