Preparation of TiO₂ thin film deposited by electrophoresis method and adsorbing dye molecules using electrophoresis method

Anatase-type TiO₂ thin films for the dye sensitized solar cell are deposited by electrophoresis method. The condition to deposit thin films of high quality is discussed. Ultra fine particles of anatase-rype TiO₂ thin film is deposited by the constant current or the constant voltage method. TiO₂ thin films of the high quality without cracks are obtained without binder using the constant current method compared with the constant voltage method. The optimum conditions of electrophoresis for constant current method are the current density I₀ from 0.03 to 0.4 mA/cm² and the deposition time from 20 to 800 s. The film thickness can be controlled by t or I₀ by specifying the concentration of colloidal solution of TiO₂. The quality of TiO₂ thin film increases for the small constant current and the long deposition time. The dye also can be adsorbed on the TiO₂ thin films by electrophoresis method. The values of the open-circuit voltage and the short-circuit current density have increased with decreasing electrophoresis current density and increasing electrophoresis time. It has been found that electrophoresis method for adsorbing dye is effective.