Stable quasi-solid-state dye-sensitized solar cell using a diamide derivative as low molecular mass organogelator

Abstract

High stability is a significant target for practical applications of dye-sensitized solar cells. 2-(1-oxododecyl)hydrazide, a diamide derivative, is synthesized and applied in quasi-solid-state dye-sensitized solar cells (QS-DSSCs) as a low molecular mass organogelator (LMOG). It is noteworthy that the transition temperature from gel state to liquid state (Tgel) of this gel electrolyte is 125.2 °C, which ensures the gel state of the electrolyte at the DSSC operating temperature. The influences of the gel electrolyte on the kinetic processes of electron transport and recombination are investigated. The diffusion of redox species in the gel electrolyte is hindered by the crosslinked network, and the decreased electron recombination lifetime indicates an increased electron recombination in QS-DSSC. Significantly, the QS-DSSC exhibits excellent thermal and light-soaking stabilities during accelerated aging tests for 1000 h. Especially, there is almost no change in the short-circuit current density (Jsc) in the QS-DSSC, while the Jsc of the liquid electrolyte based DSSC decreases to 79–90% of their initial values. These results are very important for the application and commercialization of DSSCs.