Ultra-bright pure green perovskite light-emitting diodes.

Inorganic perovskites, such as CsPbX₃ (X = Cl, Br, I), have attracted attention due to their excellent thermal stabilities and high photoluminescence quantum efficiencies. Here, we report on all-inorganic light-emitting diodes (LEDs), including inorganic perovskite emitters (CsPbBr₃) based on the heterostructure of n-ZnO/Al₂O₃/CsPbBr₃/p-GaN. The effects of the CsPbBr₃ and Al₂O₃ interlayers on the electroluminescence performance have been systematically investigated. It is observed that the Al₂O₃ interlayer plays an important role in determining the emission performance. By introducing the Al₂O₃ layers, the electron–hole recombination can almost be limited within the perovskite. The emission peaks of the heterojunction LEDs change from blue-green to pure green with the increased luminous intensities and decreased leakage currents. It provides an idea for the preparation of all-inorganic perovskite LEDs. [ABSTRACT FROM AUTHOR]