Various internal and external defects present in the perovskite film are one of the main factors that causelow efficiency and stability, and in order to realize high-performance perovskite solar cells, it is necessary...Various internal and external defects present in the perovskite film are one of the main factors that causelow efficiency and stability, and in order to realize high-performance perovskite solar cells, it is necessaryto develop a method to effectively suppress them. In this study, a heterofunctional dopants strategy wasattempted to integrate the effect of alkali metal cations (Rbþ and Kþ) and formate anion (HCOO) throughdoping engineering with alkali-metal formates, i.e., rubidium formate (RbHCOO) and potassium formate(KHCOO). Inclusive physical and photoelectric analysis revealed that doping with a small amount ofalkali-metal formate leads to crystal growth and reduction of grain boundaries, and further passivates orinhibits bulk and surface defects. As a result, the photogenerated charge recombination was reduced andthe charge carrier transport was improved, leading to improved PSC performance. RbHCOO-dopedinverted planar PSCs achieved a PCE of up to 20.41% with long-term stability. Our findings provide away for producing high-quality perovskite films with low defect densities that are essential for realizinghigh-performance PSCs.展开更多
基金supported by the Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(2020R1I1A1A01051961 and 2021R1A2C2010353).
文摘Various internal and external defects present in the perovskite film are one of the main factors that causelow efficiency and stability, and in order to realize high-performance perovskite solar cells, it is necessaryto develop a method to effectively suppress them. In this study, a heterofunctional dopants strategy wasattempted to integrate the effect of alkali metal cations (Rbþ and Kþ) and formate anion (HCOO) throughdoping engineering with alkali-metal formates, i.e., rubidium formate (RbHCOO) and potassium formate(KHCOO). Inclusive physical and photoelectric analysis revealed that doping with a small amount ofalkali-metal formate leads to crystal growth and reduction of grain boundaries, and further passivates orinhibits bulk and surface defects. As a result, the photogenerated charge recombination was reduced andthe charge carrier transport was improved, leading to improved PSC performance. RbHCOO-dopedinverted planar PSCs achieved a PCE of up to 20.41% with long-term stability. Our findings provide away for producing high-quality perovskite films with low defect densities that are essential for realizinghigh-performance PSCs.
