Enhanced performance of dye-sensitized solar cell via surface modification of mesoporous TiO2 photoanode with electrodeposited thin TiO2 layer

Surface modification of porous TiO2 photoanode with a thin compact TiO2 layer was carried out by means of anodic electrodeposition in an aqueous TiCl3 electrolyte. Results indicated that the electrodeposited thin TiO2 layer could bridge gaps between TiO2 nanoparticles and improve the electrical contact at the FTO (fluoride-doped tin oxide)/TiO2 interface, leading to an efficient electron transport. In addition, the thin compact TiO2 layer could cover the exposed surface area of FTO to the electrolyte, which contributes to the suppression of the charge recombination. The surface treatment of mesoporous TiO2 photoanode via aqueous electrochemical route is an effective way to improve the performance of DSSC (dye-sensitized solar cell), which could increase the short-circuit current density, and reduce the dark current density compared to DSSCs with bare and TiCl4-treated TiO2 photoanodes. The photoelectron conversion efficiency of DSSC was increased from 7.3 to 8.2% after employing the TiO2-modified photoanode. (C) 2011 Elsevier Ltd. All rights reserved.