A thiolate/disulfide liquid crystalline electrolyte for dye-sensitized solar cells: Promotion of the Grotthuss-type charge transport through lamellar nanostructures. (20th October 2018)

• Record Type: Journal Article
• Authors: Tan, Shuai; Zhao, Zhengshun; Wang, Caihong; Wu, Yong
• Is Part Of: Electrochimica acta. Volume 288(2018)
• Page Start: 165
• Page End: 172
• Publication Date: 2018-10-20
• Subjects: Liquid crystalline electrolyte -- Thiolate/disulfide redox couple -- Lamellar nanostructures -- Charge transport -- Dye-sensitized solar cells; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2018.09.003
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: Smectic 1-dodecyl-3-methyl-1H-imidazol-3-ium 1-methyl-1H-tetrazole-5thiolate ([C12 MIm][T]) has been prepared for dye-sensitized solar cells (DSSCs). The electrolyte consisting of [C12 MIm][T] and di-5-(1-methyltetrazole) disulfide (T2 ) with mole ratio 2:1 exhibited smectic A (SA ) liquid crystal phase over a temperature range from 12.5–75.5 °C. A bilayer nanostructure formed in the SA phase and the T − /T2 redox couple was intercalated between the smectic layers. Photovoltaic characterization revealed that the power conversion efficiency of the smectic T − /T2 DSSC increased with the increase in temperature and reached 4.1% at 70 °C under simulated AM1.5G solar light. Regression analysis of temperature dependent charge diffusion coefficients and viscosities suggested that the charge transport in the T − /T2 electrolyte was dominated by the Grotthuss-type exchange reaction. The lamellar nanostructure of T − /T2 promoted the Grotthuss-type charge transport and improved the DSSC performance. The ordered arrangement of the redox couple offers an effective way to enhance the charge transport for the DSSC electrolytes unfavorable for physical ion diffusion. Graphical abstract: A thiolate/disulfide liquid crystalline electrolyte enhanced performance of dye-sensitized solar cells through the facilitated Grotthuss-type exchange reaction. Highlights: A thiolate/disulfide liquid crystalline electrolyte was prepared for DSSC. The thiolate ions and disulfide aggregated into lamellar assembly. The lamellar nanostructures promoted the Grotthuss-type charge transport. The mesomorphic electrolyte enhanced DSSC performance at elevated temperatures.