Submillimeter and lead-free Cs3Sb2Br9perovskite nanoflakes: inverse temperature crystallization growth and application for ultrasensitive photodetectors

Lead-free Cs3Sb2Br9 perovskites demonstrate wide applications in photodetectors owing to their remarkable optical properties and nontoxicity. Herein, we utilized an inverse temperature crystallization strategy to synthesize submillimeter Cs3Sb2Br9 perovskite nanoflakes. The carrier relaxation dynamics was investigated. Moreover, the Cs3Sb2Br9 perovskite nanoflake device exhibits fast response speed, high responsivity and excellent detectivity.