The investigation on different light harvesting layers and their sufficient effect on the photovoltaic characteristics in dye sensitized solar cell

Titanium dioxide-based nanofibers (TiO2 nanofiber) were prepared by an electrospinning technique. The electrospun composite fibers were synthesized at different concentrations of titanium isopropoxide (25.35, 50.69, 76.05 wt%) and calcinated at different temperatures (450 oC, 650 oC and 850 oC) for 2 h. The diameters of nanofibers decreased by increasing the inorganic part of composite nanofibers and principally depicted anatase, anatase- rutile and rutile phases. By increasing temperature from 450 oC to 850 oC, the anatase phase decreased whereas the rutile phase increased. The different optimized TiO2 nanofibers were prepared and utilized as a sufficient scattering layer for the photoanode in dye sensitized solar cells. Then, the electron transport and recombination in TiO2 nanofiber based dye sensitized solar cells (DSSCs) was investigated. It was shown that the electron life time in DSSCs with TiO2 nanofibers, as a scattering layer, increases in different photoanode electrodes compared to that on DSSCs based on nanoparticles. As a result, conversion efficiency of 5.6% is realized, which is 55.37% higher than TiO2 photoanodes without addition of nanofibers as a scattering layer.