Low molecular mass organogelator based gel electrolyte gelated by a quaternary ammonium halide salt for quasi-solid-state dye-sensitized solar cells

Quasi-solid-state dye-sensitized solar cells (DSC) are fabricated using tetradodecylammonium bromide as a low molecular mass organogelator (LMOG) to form gel electrolyte with a high solution-to-gel transition temperature (T-SG) of 75 degrees C to hinder flow and volatilization of the liquid. The steady-state voltammograms reveal that the diffusion of the I-3(-) and I- in the gel electrolyte is hindered by the self-assembled network of the gel. An increased interfacial exchange current density (j(o)) of 4.95 x 10(-8) A cm(-2) and a decreased electron recombination lifetime (tau) of 117 ms reveal an increased electron recombination at the dyed TiO2 photoelectrode/electrolyte interface in the DSC after gelation. The results of the accelerated aging tests show that the gel electrolyte based dye-sensitized solar cell can retain over 93% of its initial photoelectric conversion efficiency value after successive heating at 60 degrees C for 1000 h, and device degradation is negligible after one sun light soaking with UV cutoff filter for 1000 h. (C) 2010 Elsevier B.V. All rights reserved.