초록 |
Fully-inorganic CsPbI3 quantum dots (CsPbI3-QDs) are used as a promising photovoltaic absorber showing the high device performance in QD solar cells. However, low stability of cubic-phase CsPbI3 QDs has been pointed out as a problem that makes difficult for photovoltaics application. In the previous studies, many researchers used compact TiO2 (c-TiO2) as an electron transport layer (ETL) in CsPbI3-QD solar cells, which have several limitations such as high-temperature process and low electron mobility. In addition, we newly found that c-TiO2 ETL can induce the cubic-phase degradation of CsPbI3-QDs. To address these issues, we introduced a new strategy for ETL of CsPbI3-QD solar cells by using SnO2 QDs instead of c-TiO2. We showed that the SnO2 enables to maintain the stable cubic-phase of CsPbI3-QDs under humid and illumination conditions. Consequently, we believe that our new approach can provide insights that will help development of highly efficient and stable CsPbI3-QD solar cells. |