Synthesis of Hybrid Tin‐Based Perovskite Microcrystals for LED Applications

Abstract Considerable focus on tin‐based perovskites lies on substitution to leadhalide perovskites for the fabrication of eco‐friendly optoelectronic devices.The major concern related to tin‐based perovskite devices are mainly thestability and the efficiency. However, thinking on the final commercializationscope, other considerations such as precursor stability and cost are majorfactors to carry about. In this regard, this work presents a robust and facilesynthesis of 2D A2SnX4 (A = 4‐fluorophenethylammonium(4‐FPEA); X = I, Br, I/Br) and 3D FASnI 3 perovskite microcrystals followinga developed synthesis strategy with low‐cost starting materials. In thisdeveloped methodology, acetic acid is used as a solvent, which helps to protectfrom water by making a hydrophobic network over the perovskite surface, andhence provides sufficient ambient and long‐term inert atmosphere stability ofthe microcrystals. Further, the microcrystals are recrystallized in thin filmsfor LED application, allowing the fabrication of orange, near‐infrared and purered emitting LEDs. The two‐step recrystallized devices show better performanceand stability in comparison to the reference devices made by using commercialprecursors. Importantly, the developed synthesis methodology is defined as ageneric method for the preparation of varieties of hybrid tin‐based perovskitesmicrocrystals and application in optoelectronic devices.