The reversal constituent structure of photo-electrode in dye-sensitized solar cells

This article presents significant experimental data about the dye-sensitized nano solar cells (DSSCs) using the new developed photo-electrode with reversal constituent structure in our CCT laboratory. The conventional constituent structure of a photo-electrode arranged in sequence from the incident light is the transparent conductive glass, the nano TiO2 semi-conductive porous film, and the dye. In process, the photons energy of the incident light is mainly absorbed by the dye for DSSCs. This causes excited electrons in the dye to jump into conductive band of the TiO2 and further to transfer into the outer circuit through the conductive glass. That is, a correct constituent structure of the photo-electrode arranged in sequence from the incident light in terms of the working principle should be the dye, the nano TiO2 film, and the conductive substrate. The conventional constituent structure of the photo-electrode causes the incident light to be hindered by the TiO2 layer. To reduce the light hindrance for the dye, this work used copper mesh as the conductive substrate and the nano TiO2 was coated on it. In this way, the copper mesh connects the nano TiO2 layer with the outer circuit and the holes of the copper mesh also allow the dye to contact with the electrolyte. The new developed constituent structure of the photo-electrode arranged in sequence from the incident light is the dye, the nano TiO2 film, and the copper mesh. This new constituent structure, which increases amounts of the absorption light in the dye and further improved the short-circuit current as well as the photoelectric conversion efficiency of DSSCs is reverse to the conventional constituent structure.

► The new structure of photo-electrode in DSSC increases absorption of incident photons.
► The substrate of copper mesh as photo-electrode reduces electric resistance.
► Application of the copper mesh as substrate reduces the fabricating cost.
► There are ca. 3 times increment of photoelectric conversion efficiency.
► Application of the copper mesh as substrate can achieve the flexible DSSCs.