Towards a high open-circuit voltage by co-additives in electrolyte for high-efficiency dye-sensitized solar cells

The co-additives of benzimidazole and 2-ethylimidazole in electrolyte have an obvious effect on the performance of dye-sensitized solar cells due to their good coordination ability of titanium dioxide, which could affect the energy levels and charge transfer process. Through a balance of the concentrations, the best efficiency of 7.93% with a high open-circuit voltage of 0.817 V is achieved for a cell fabricated with the electrolyte contains benzimidazole and 2-ehtylimidazole by a molar ratio of 9.5/0.5.