A supramolecular gel electrolyte formed from amide based co-gelator for quasi-solid-state dye-sensitized solar cell with boosted electron kinetic processes

Abstract

Abstract A supramolecular gel electrolyte ( T gel > 100 °C) is formed from N,N ′-1,8-octanediylbis-dodecanamide and iodoacetamide as two-component co-gelator, and introduced into the quasi-solid-state dye-sensitized solar cells (QS-DSSCs). The different morphologies of microscopic network between two-component and single-component gel electrolytes have influence on the diffusion of redox couple in gel electrolytes and further affect the electron kinetic processes in QS-DSSCs. Compared with the single-component gel electrolyte, the two-component gel electrolyte has less compact gel network and weaker steric hindrance effect, which provides more effective charge transport channel for the diffusion of I 3 /I − redox couple. Meanwhile, the NH 2 groups of iodoacetamide molecules interact with Li + and I 3 − , which also accelerate the transport of I 3 − /I − and decrease in the I 3 − concentration in the TiO 2 /electrolyte interface. As a result, nearly a 12% improvement in short-circuit photocurrent density ( J sc ) and much higher open circuit potential ( V oc ) are found in the two-component gel electrolyte based QS-DSSC. Consequently, the QS-DSSC based on the supramolecular gel electrolyte obtains a 17% enhancement in the photoelectric conversion efficiency (7.32%) in comparison with the QS-DSSC based on the single-component gel electrolyte (6.24%). Furthermore, the degradations of these QS-DSSCs are negligible after one sun light soaking with UV cutoff filter at 50 °C for 1000 h.