The effects of the dye-adsorption solvent on the performances of the dye-sensitized solar cells (DSSCs) based on black dye have been investigated. The highest conversion efficiency (10.6 %) was obtained in the cases for which 1-PrOH and the mixed solvent of EtOH and tBuOH (3:1 v/v) were employed as dye-adsorption solvents. The optimized value for the dielectric constant of the dye-adsorption solvent was found to be around 20. The DSSCs that used MeOH as a dye-adsorption solvent showed inferior solar-cell performance relative to the DSSCs that used EtOH, 1-PrOH, 2-PrOH, and 1-BuOH. Photo- and electrochemical measurements of black dye both in solution and adsorbed onto the TiO 2 surface revealed that black dye aggregates at the TiO 2 surface during the adsorption process in the case for MeOH. Both the shorter electron lifetime in the TiO 2 photoelectrode and the greater resistance in the TiO 2-dye-elecrolyte interface, attributed to the dye aggregation at the TiO 2 surface, cause the decrease in the solar-cell performance of the DSSC that used MeOH as a dye adsorption solvent. Black power: The conversion efficiency of the dye-sensitized solar cell based on black dye (see figure) strongly depends on the dielectric constant of the dye-adsorption solvent.
All Science Journal Classification (ASJC) codes
- Organic Chemistry