Effect of TiO₂ photoelectrode thickness on the performance of dye-sensitized solar cells

TiO₂ photoelectrodes for dye-sensitized solar cells (DSSCs) were fabricated by changing the thickness using screen printing method. The amount of dye adsorbed on TiO₂ increases as the thickness of the TiO₂ photoelectrode increases because of the increase in the dye molecule adsorption site. The performance of DSSCs increases up to a TiO₂ thickness of approximately 12 μm, indicating a tendency of dye adsorption that enables photocurrent generation. However, when TiO₂ is thicker than 12 μm, the TiO₂ films start to break, resulting in a decrease in the performance. The optimum thickness of the TiO₂ photoelectrode was 12 μm, which has a low charge transfer resistance.