Low-temperature preparation of dye-sensitized solar cells through crystal growth of anatase titania in aqueous solutions

Crystal growth of anatase-type titania in aqueous solutions of titanium tetrafluoride and titanyl sulfate at 60 °C was applied for low-temperature preparation of dye-sensitized solar cells. Crystalline titania films grown on a transparent conducting substrate were directly utilized as a photoelectrode for the solar cells. The improvement of porous electrodes consisting of titania nanoparticles was also achieved through subsequent grain growth and neck formation in the solutions. The maximum efficiency of the photovoltaic performance obtained by the low-temperature processes was almost equal to that with a conventional heating procedure.