An Investigation of the Fill Factor and Efficiency of Molecular Semiconductor Solar Cells

This study investigated and calculated the fill factor and efficiency of N719 and D149 organic dyes in titanium dioxide (TiO 2 ) solar cell systems using a current equation that we derived using a quantum transition-state theory (TST). The theory of charge transfer reactions was used to investigate the electronic current to enhance both the fill factor and efficiency of both N719/ and D149/TiO 2 solar cell systems. The current calculated for Di-terabtylammoniumcis-bis (isthiocyanato) bis (2,2-bipyridyl-4,4dicarboxylato) ruthenicyanatoum (II)(N719) and 5-[[4-[4-(2,2-Diphenylethenyl) phenyl]-1,2,3-3a,4,8b-hexahydrocyclopent [ b ] indol-7-yl] methylene]-2-(3-ethyl-4-oxo-2-thioxo-5-thiazolidinylidene)-4-oxo-3-thiazolidineacetic acid indicated that the molecules of D149, an indoline-based dye, have to be in contact with the semiconductor due to the quantum donor-acceptor scenario model. The efficiency of N719/and D149/TiO 2 solar cells were significantly affected due to transition energy, which is caused by the mechanisms of the charge transfer process. Solvents; such as trifluoroethanol (C 2 H 3 F 3 O), propanol (C3H8O), ethanol (C 2 H 5 OH), and acetonitrile (C2H3N); were used to determine the current, fill factor, and efficiency. Coefficients of charge transfer; such as transition energy, barrier, driving force energy, current, power-conversion efficiency, fill factor (FF), and efficiency; were evaluated theoretically. The current of the N719/ system with acetonitrile and ethanol solvents was higher than current of the N719/ system with trifluoroethanol and propanol solvents. While the current of the D149/ system with trifluoroethanol and propanol solvents was higher than current of the D149/ system with acetonitrile and ethanol solvents. The current and transition energy efficiencies of both systems varied. devices were found to have the best power conversion efficiency and low transition energies while the power conversion efficiency was large for devices with sizeable current density and activity with lower transition energies. Keywords: Fill Factor, Efficiency, Molecule/Semiconductor, Solar Cells.