Studies On The Preparation And Properties Of Photoanode Materials For Use In Dye-sensitized Solar Cells

In this paper, the preparation technology of dye-sensitized solar cells wasresearched, and ruthenium bipyridine and porphyrine based solar cells were fabricatedbased on the photoelectrode and TiO2withdifferent structure. The photoelectricconversion efficiency was rasied by improving their material, optical andelectricchemical property.The paste made in P25was controlled by choosing different solvent anddispersion method for its uniformed nature. And high-effciency dye sensitied solarcells was fabricated in screen-printing method by improving the coating method andthickness.The dye sensitized solar cells with scattering center gradual increasing werefabricated in the TiO2block synthesized by micro-emulsion method, and theirphotoelectric conversion efficiency was7.34%, which was20.43%higher than thecell with ordinary photoelectrode made in P25. And the prophyrine type solar cellswith scattering center gradual increasing was prepared by using porphyrine-1assensitizer, which conversion efficiency was7.34%. Though comparing the parameter,the structure with scattering center gradual increasing was more efficiency forprophyrine type solar cells, which is21.34%higher than ordinary cells.Semiconductor films with different pore size were perared by templating method.And through comparing their material and optical property, their features ofincreasing the optical absorption and diffuse reflection was affected by increasing thephotoelectric conversion efficiency of the cell with pores size gradul increasing is thehighest in their counter group, which is7.80%. The followed A.C. impendancemeasurement demonstrated that the structure of pores size gradul increasing was anefficiny model for electrolyte penetration, and then leads higher conversion efficiency.In addition, porphyrine-2was chose as sensitizer for prepared dye sensitized solar cell,and the conversion efficiency is6.01%, which made such type solar cells gets morespace for improving.The TiO2with different structure and similar size were synthesis by variousmethods. And the dye sensitized solar cells were fabricated with above TiO2forabsorption layer or scattering layer, then measured and compared their photovoltaic performance. From the result, submicro TiO2was most suitable for working asscattering layer, and the highest efficieny of cell with this scattering layer is6.21%.The electrichemical measurement reveals that TiO2with continuous structure wouldaccelerate the speed of electron transport. The porphyrine type solar cells withdifferent structure were fabricated by using porphyrine-3as sensitizer. All thesesubmicro materials could work as efficient scatters, and their effect would better thanRu complex sensitized solar cells. The reason of the higher efficiency was detected byquantum yield measurement, that the absorption defect of prophyrine at500nm wouldcompensate by the scatter effect in450-600nm.The hierarchical spheres synthesis by simple method would obtain TiO2ofanatase with little brookit, and the diameter of the spheres would control by adjust theamount of urea and PVP. The alkalinity of solvent would raise by adding urea, and thesize of spheres would get larger; PVP would bind the spheres from getting larger, theirdosage were inversely with the diameter of spheres. Additionally, the photoelectricconversion efficieny of cells made by above hierarchical spheres woud get6.61%,which is higher than any submicro material used in our study. That means thehierarchical spheres synthesis by simple method was one of most suitable material forfabricating the semiconduct layer of dye sensitized solar cells.