Fabrication of fibrous films with rugate structure prepared by layer-by-layer self-assembly method: Application to photoelectrode of dye-sensitized solar cell

In this study, we report the fabrication of anatase TiO2 film with high porosity and large surface area by using a new fibrous replica prepared by layer-by-layer self-assembly technique. The scanning electron microscope photographs revealed that the fibrous replica with a rugate structure was obtained by immersing a flat polymer film into a SA solution. By using the fabricated porous TiO2 film with ca. 4.5 μm of film thickness as the photoelectrode for dye-sensitized solar cell, the photocurrent–voltage characteristic in an energy conversion efficiency (Eff) was improved from Eff = 1.49% to Eff = 3.53%, because the amount of loaded dye absorbed on porous TiO2 film was increased.