| 초록 |
Great improvements in performance of perovskite solar cells (PSCs) over the past few years, thanks to the development of fabrication protocols, chemical compositions and phase stabilization methods, have made PSCs one of the most efficient and low-cost solution-processable photovoltaic technologies. However, the light-harvesting performance of these devices is still limited by excessive charge carrier recombination. Despite much effort, the performance of the best-performing PSCs is capped by relatively low fill factors and high open-circuit voltage deficits (the radiative open-circuit voltage limit minus the high open-circuit voltage). In this study, we report a holistic approach to improving the performance of PSCs through enhanced charge carrier management. First, we develop a metal oxide electron transport layer with an ideal film coverage, thickness and composition by tuning the chemical bath deposition of tin dioxide (SnO2). Second, we decouple the passivation strategy between the bulk and the interface, leading to improved properties, while minimizing the bandgap penalty. In forward bias, our devices exhibit an electroluminescence external quantum efficiency of up to 17.2%. As solar cells, they achieve a certified power conversion efficiency of 25.2%, corresponding to 80.5% of the thermodynamic limit of its bandgap. |
