Published online by Cambridge University Press: 01 February 2011
The photovoltaic properties of dye-sensitized solar cells (DSCs) based on fluorine doped tin oxide (FTO) and Ti substrates were investigated. The sheet resistances of the substrates were correlated to the photovoltaic properties. The efficiency of the Ti substrate based DSC was higher than that of the FTO substrate based DSC, due to a high fill factor (FF). To minimize the internal resistance of the DSCs, Ti plate was used as a support for nanocrystalline TiO2, because of its low sheet resistance. As the light was absorbed by the electrolyte layer, the incident photon to current efficiency (IPCE) values decreased in the range between 400-600 nm. The electrolyte concentrations were optimized to obtain a higher cell performance. When using an electrolyte composed of 0.02 M I2, 0.2 M LiI, and 0.5 M 4-tert-butylpyridine, an efficiency of 4.98% was obtained for the Ti substrate based DSC with a short circuit current density (Jsc) of 11.25 mAcm-2, an open circuit voltage (Voc) of 0.692 V, and a FF of 0.639. The effect of the cell size on the photovoltaic properties was also investigated. The rate of decrease in a FF and efficiency with increase in the cell size was lower for the Ti substrate based DSCs than the FTO substrate based DSCs. This result indicates that Ti plate is a potential candidate for production of large DSCs.