CsPbBr₃/CH₃NH₃PbCl₃ Double\nLayer Enhances Efficiency and Lifetime of Perovskite\nLight-Emitting Diodes

Abstract

At\npresent, perovskite light-emitting diodes are mostly based on\nvarious forms of nanostructures exploiting their exciton confinement\nproperty. However, the few reports utilizing bulk or polycrystalline\nperovskites have been limited in application because of the difficulties\nof forming high-quality films, especially on the existing organic\ncharge transport layers. When these charge transport organics are\nexchanged with thicker CH₃NH₃PbCl₃, the emitting CsPbBr₃ thick polycrystalline films containing\nCH₃NH₃Br are conformally deposited with improved\nluminescence quality without driving voltage increase. Enhanced crystallinity\nand prolonged photoluminescence are observed by exploiting interfacial\ndefect passivation and the strain-induced effect in the heterostructures.\nThis approach could lead to high-performance light-emitting diodes\nand may also be extended to other perovskite devices.