The current-voltage characteristics of dye-sensitized porous-TiO2 (por
-TiO2) solar cells are investigated in the dark and under illumination
at light intensities up to 1500 W/m(2) and temperatures between -5 an
d 80 degrees C. In the dark, the barrier height and the ideality facto
r of the por-TiO2/electrolyte contact are 0.67 eV and 1.05, respective
ly. The very low effective Richardson constant indicates the importanc
e of diffusion for transport. A current-dependent effective barrier he
ight has been established under illumination of dye-sensitized por-TiO
2 solar cells. The barrier lowering effect should be caused by the low
neutralization rate of the positively charged dye radicals in the ele
ctrolyte. (C) 1998 American Institute of Physics. [S0003-6951(98)02337
-7].