Enhancement of the performance of perovskite solar cells via the modification of electron transport layers with polyaniline

Among the various electron transport layers used in perovskite solar cells, titanium oxide (TiO2) is by far the most efficient electron transfer layer. But the high recombination of electrons and holes in the titanium oxide layer is a problem that researchers face. Researchers have tried to solve this problem by doping various additives in this layer. In this study, for modification this defect, polyaniline was added to the precursor of the titanium oxide mesoporous layer (mP-TiO2) to improve the performance of the perovskite methyl ammonium solar cell. Scanning electron microscopy images showed the morphology, crystallinity, and coverage of the perovskite film deposited on the mP-TiO2 substrate doped with polyaniline at volume ratios of 2%, 4%, and 8% compared with the perovskite film deposited on Pure mP-TiO2 substrate have improved. By adding polyaniline to the mP-TiO2 layer with different volume ratios, open circuit current density(J_SC) and charge factor (FF) were increased. The increase in these parameters is due to the reduction of recombination at the TiO2 / perovskite interface as well as reduction of charge traps, which improve cell performance. Cells made on the modified mP-TiO2 substrate with a volume ratio of 4% polyaniline show the best morphology, crystallinity and performance(7.31%).