Organic solvent based TiO2 dispersion paste for dye-sensitized solar cells prepared by industrial production level procedure

In order to prepare the TiO2 liquid dispersions for the electrodes of dye-sensitized solar cells with industrial mass production level at a reasonable cost, the present study investigates the preparation of TiO2 liquid dispersions by a general industrial dispersion technique using readily available P25. To determine the TiO2 dispersion offering the best light-electricity energy conversion efficiency, the suitability of various types of solvents and resins for use in TiO2 dispersion are tested. In general, organic solvent based TiO2 dispersions are found to allow the formation of more uniform thin films in comparison with water-based dispersions. A preparation using ethyl cellulose as the resin and the terpineol as the solvent is found to exhibit the best conversion efficiency. We have also found that using two kinds of resins of different molecular weights gave rise to better efficiency. Among 26 metal compounds tested in this study, the best metal dopant was Ag. XRD and XPS measurements confirm that the Ag exists as metal Ag and silver oxide.