Authors

• M. Hosseinnezhad ^{1, 2}
• K. Gharanjig ^{1, 2}

¹ Institute for Color Science and Technology, Department of Organic Colorants, Tehran, Iran.

² Institute for Color Science and Technology, Center of Excellence of Color Science and Technology, Tehran, Iran.

Abstract

Two organic dyes based on indoline were prepared as photosensitizer contain phenothiazine as the electron donor group and acrylic acid (Dye 1) and cyanoacrylic acid (Dye 2) as the electron acceptor anchoring. Spectrophotometric measurements of the synthesized dyes in solution and on a ZnO substrate were carried out in order to assess changes in the status of the dyes. The wavelength of maximum absorption of dye 1 and dye 2 in solution are 412 nm and 424 nm and on ZnO films are 429 nm and 438 nm, respectively. Maximum dye adsorption time around 10h could be utilized with minimum aggregation or precipitation of the dye on photoelectrode substrate. The effect of Li ions and composition of the iodide/triiodide based electrolyte on the performance of DSSCs were investigated. A high concentration of Li ions in electrolyte was found to be shift the ZnO conduction band edge to more negative potentials that have a direct effect on recombination phenomena. The Maximum conversion efficiency was achieved for dye 2 in the presence of 1mM Li ions around 5.17%.

Keywords

• Indoline
• Dye-sensitized solar cell
• ZnO
• Electrolyte