Abstract
Metal oxide semiconductor nanofibers obtained by electrospinning are excessively used in organic-inorganic photovoltaic
(PV) devices due to large surface area with low production cost. Performance of these devices depends upon the thickness of the active
layer and polymer infiltration through the pores of nanofibers mat, which is controlled by electrospinning time. The parameters of hybrid
photovoltaic devices, fabricated by poly (3-hexylthiophene) (P3HT) and TiO2/ Di-tetrabutylammonium cis-bis(isothiocyanato)bis(2,2 -
bipyridyl-4,4 -dicarboxylato)ruthenium(II) (N719) composite nanofibers was analyzed by considering infiltration of polymer through the
electrospun nanofibrous network. Power conversion efficiency (PCE) was improved from 0.13% to 0.93%. Open circuit voltage and
short circuit current density were also improved to 0.61V and 3.64mA/cm2 respectively. Longer electrospinning time resulted in an increased
number of fiber layers, i.e. increased thickness of the active layer. This results in higher light absorption but reduced infiltration
of polymer through the nanofibrous pores up to the lowest layer due to covering up by the top layers. These factors introduce defects and
increased series resistance, contributing toward decrease in device efficiency.