Abstract
A supramolecular gel electrolyte (T-gel > 100 degrees 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 -NH2 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 TiO2/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 degrees C for 1000 h. (C) 2017 Elsevier B.V. All rights reserved.