Synthesis Of Nanostructural TiO₂ And Its Photovoltaic Perproties For Dye-Sensitized Solar Cells

As a low-cost alternative to convertional silico-based photovoltaic devices, dye-sensitized soalr cells (DSSCs) have attracted much attention and the best efficiency of 12.3% has been achived. Such a solar cell has also been regarded as the domination of photovoltaic devices in the next gerenation.The aim of this thesis is to fabricate the high efficient DSSCs based on nanostructral TiO2. In the present work, a series of nanostructural TiO2 have been synthesized and then used as the photoanodes for DSSCs. Furthermore, the relationships between the photovoltaic properties and the instrinic characteristics of nanomaterials have also be investigated in detail.(1) TiO2 nanosheets were successfully synthesized using a simple hydrothermal route and then used as an electrode material for DSSCs. The influences of film thickness, sensitizer and calcination time on the photovoltaic performances were also investigated. It was found that the N719 dye-sensitized solar cell showed the best efficiency of 5.27%.(2) TiO2 nanotubeswith a large surface area were successfully synthesized and used as the electrode materias for DSSCs. A cell composed of the calcined nanotubes exhibited an efficiency of 7.0%. It was found that the crystallinity and film quality of TiO2 can be enhanced using the calcined nanotubes as an electrode material.(3) The electrode film were prepared with TiO2 nanoparticles and nanotubes using a screen printer via layer by layer, and then applied in DSSCs. After the film surface was treated and impregnated in a mixed dye solution of N719 and D131, the cells were fabricated. It was found that the best efficiency of 8.44% was achieved.