Abstract:
This study focuses on influence of interface
modifiers on hole mobility in Hybrid Nanoporous Titanium
dioxide (TiO2) / Poly(3-hexylthiophene) (P3HT) nanocomposite
by using time of flight technique. We found that the hole-mobility
in the composite material is more than two orders of magnitude
less than that of pristine P3HT. This may be due to poor polymer
infiltration of the polymer into highly structured porous TiO2.
However, hole-mobility of the polymer in TiO2:P3HT is increased
to an order of magnitude when ruthenium based dye either Z907
or N719 is introduced at the TiO2/P3HT interface. This is
consistent with corresponding current density (J) – voltage (V)
charateristics of thin TiO2 / P3HT devices with or without dye
interface layer. Better JV characteristics of the device and higher
hole mobility of P3HT found in TiO2 / dye / P3HT may be due to
passivation of surface traps by the dye.
