In this study, we investigated the rate of exciton formation and dissociation in TiO2/Si/porphyrins hybrid solar cells in different phases. Using different porphyrin-based donors in four sets, it was found the best hybrid architectures belong the donors containing metal and alkyl group and those exposed the solvents. The proper kinetic of the excitonic processes in these hybrid solar cells are originated from lower affinity energy and exciton binding energy of their donors. Also, donors with the lowest energy barrier of electron injection as well as the highest excitonic Bohr radius showed the excitons can be dissociated in the dye/semiconductors interface, easily. The analysis of the probable correlations between the molecular descriptors and kinetic parameters of the excitons presented more credible evidences about the solvent and metal effects on the photovoltaic processes. Finally, based on the other performance characters of these solar cells, it was concluded that maximum value of the external quantum efficiency belongs to the metalloporphyrins in the solvent media.

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