A study of the anodizing of titanium for dye-sensitized solar cells

Titanium (Ti) is a common anode substrates for dye-sensitized solar cells (DSSCs), which is flexible, has good resistance to corrosion, and electrical conductivity. However, Ti is not transparent and the resultant DSSC requires rear illumination. In order to improve the photovoltaic performance, anodizing oxide technology (AOT) is used to modify the Ti substrate [1-3]. The color of Ti surface then changes from silver to purple because a reflective Ti oxide layer forms on the substrate surface. The surface Ti oxide layer acts as a blocking layer, which goes better charge recombination for the anode [3]. The power conversion efficiency of the DSSC increases from 2.61 to 3.65 % after the AOT treatment. The improvement in the efficiency is attributed to an improvement in the short-circuit current density.