Optimization of Sn-based perovskite solar cells with the antisolvent doped by acetaldoxime

The process of the antisolvent rinsing plays an important role during the formation of the perovskite crystals. Since the function of the single-component antisolvent may be limited, a reducing agent named acetaldoxime (AO) was applied as the additive for the antisolvent. The analysis of both the surface morphology and the crystal structure indicates that AO can effectively improve the quality of the FASnI 3 perovskite film. The defects of the perovskite film can be greatly suppressed. Moreover, due to the increase of the crystal grain size with the surface roughness reducing at the same time, the charge recombination resistance of the FASnI 3 perovskite film increases. Therefore, the devices modified by AO have higher short-circuit current, fill factor as well as power conversion efficiency. At the same time, the surface of the FASnI 3 perovskite film becomes more hydrophobic, which benefits impeding the permeation of the ambient vapor into the perovskite film. The results of lifetime testing show that the stability of the devices is greatly improved.