ScholarWorks@숙명여자대학교

초록

The p-type Nickel oxide (NiOx) is a promising alternative hole transport material for perovskite solar cells (PSCs), exhibiting high stability, low cost, facile processing, and excellent electrical and optical properties. However, NiOx has not been widely used for narrow-bandgap (NBG) PSCs due to some limitations. Here, we demonstrate modifying electrical properties of solution-processed NiOx film via lithium doping to facilitate charge transfer at the NiOx/(FASnI3)0.6(MAPbI3)0.4 interface. The initially unfavorable valence band maximum (VBM) of NiOx shifts upward and become well aligned with that of NBG (Eg=1.24 eV) perovskite. Li doping does not affect the morphology or crystallographic properties of the perovskite; however, the improved conductivity due to increased charge carrier concentration facilitates efficient charge transfer at the interfaces. We found that the photovoltaic performance was improved by enhanced charge extraction, with 20 mol% Li doping identified as the optimal condition. After treatment with a diluted Poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) solution, all solar cell parameters are further improved, achieving PCE of 15.33 %.

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