Modulated growth of high-quality CsPbI3 perovskite film using a molybdenum modified SnO2 layer for highly efficient solar cells

The electron transport layer (ETL) plays a critical role in charge extraction and perovskite thin film growth in planar n-i-p heterojunction perovskite solar cells. Herein, we modulated the nucleation and growth rate of CsPbI3 crystals by using a Mo doping strategy to synthesize high-quality SnO2 crystals as an ETL nano-film in n-i-p heterojunction perovskite solar cells. We revealed that such a nano-film with low surface energy and high roughness induced by Mo doping provides seed-like nucleation sites for CsPbI3 inorganic perovskite growth, leading to improved perovskite film morphology. The charge extraction at the ETL/perovskite interface is also enhanced due to the improved energy level alignment. As a result, a high power conversion efficiency of 17.41% can be achieved under one sun irradiation for a planar n-i-p heterojunction structured CsPbI3 solar cell by using this novel Mo-SnO2 ETL. This work provides a simple pathway to simultaneously modulate CsPbI3 inorganic perovskite crystallization and interfacial charge extraction in planar heterojunction perovskite devices.

Automated summary

The study synthesized high-quality SnO2 crystals as an ETL nano-film for solar cells using a Mo doping strategy, providing a simple pathway to simultaneously modulate CsPbI3 inorganic perovskite crystallization and interfacial charge extraction, leading to improved performance.