Synergistic Buried and Bulk Engineering by Pre-Crystallized 2D Seeds Enables High Performance Inverted Perovskite...

The pursuit of high-performance perovskite photovoltaics necessitates precise control over crystal growth. While surface defects have been extensively investigated, the regulation of buried interface and crystal orientation in three-dimensional (3D) perovskites is equally critical for high-performance inverted perovskite solar cells (PSCs). Herein, we report a synergistic strategy that enhances buried interface contact and directs bulk crystallization by incorporating DFBP₂PbI₄ two-dimensional (2D) perovskite crystal seeds. It is revealed that the molecularly tailored 2D seeds not only promote bottom-up epitaxial growth of perovskite films with a favored crystallization direction but also form hydrogen bonds with the self-assembled monolayer (SAM), thereby accelerating interfacial carrier transfer. Consequently, the optimized inverted PSCs achieve a champion power conversion efficiency of 25.40% and exhibit remarkable operational stability, retaining 91.7% of their initial efficiency after 800 h of continuous operation at the maximum power point tracking. Our findings underscore the importance of co-optimizing buried interfaces and bulk crystallographic order to advance the performance of PSCs.