Structure design of nano-TiO2 electrode in dye-sensitized solar cells

In dye-sensitized solar cells (DSSCs), the physical properties and microstructure of nano-titanium dioxide film electrode are the key factors to influence the photo-electric characters greatly and they are also determined by the preparation techniques. A new electrode of double-layer TiO2 with different structure was designed and prepared by spin-coating and screen-printing techniques alternately. Such two types of layers have different contribution to the photo-electric conversion functions. Compact TiO2 film made by spin-coating only absorbs little dyes, but it works as a barrier layer between ITO and electrolyte. The porous TiO2 film made by screen-printing will absorb more dyes, and results in higher photocurrent. At the end, the effect of the compact layer on I-V properties of the DSSCs was discussed.