Improved performance of dye-sensitized solar cells by employing acid treated Ti layer on the nanocrystalline TiO2

• The effect of TiO2-dye interfacial layer was investigated.
• This layer was deposited by Titanium sputtering and oxidized by post-treatment.
• Optimized surface enhanced dye loading and short circuit current density.
• Efficiency of dye-sensitized solar cells employing interfacial layer was improved.

The effects of a titanium (Ti) layer, which was deposited by direct current magnetron sputtering and treated with acid, on a nanocrystalline TiO2 photoelectrode for dye-sensitized solar cells (DSSCs) were investigated. Dipping in the hydrochloric acid solution for various times followed by sintering resulted in a change in surface morphology, which affected the photovoltaic performance of DSSCs. Post-treatment under the appropriate conditions resulted in the formation of uniformly dispersed surface aggregates with concomitant increase in dye absorption, which led to the enhancement of short circuit current density. The optimal acid processing time was 5 min for Type 1, whose efficiency was 6.91%. The effects of the added Ti layer were examined using a range of techniques.