Stable CsPbI3 Nanoplatelets with Tunable Morphologies and Dimensions for Red Light-Emitting Diodes.

Red-emitting CsPbI₃ perovskite materials are still limited in various commercial applications because of their stability being related to the morphology and dimension. In this paper, a solvothermal method was developed to fabricate CsPbI₃ perovskite nanomaterials with governable morphologies (e.g., nanoplatelets (NPLs) to nanocubes (NCs)) and dimensions ranging from the zero-dimensional (0D) Cs₄PbI₆ to the three-dimensional (3D) CsPbI₃. By adjusting the amount of Cs precursor solutions, the photoluminescence (PL) peak position of the samples was tuned over the whole red-emitting region (from 607 to 700 nm). In addition, the reaction temperature affected the PL properties of the samples and demonstrated that temperature was critical to control the performance of CsPbI₃ perovskite materials. Furthermore, sodium dodecyl benzene sulfonate (SDBS) was chosen as the additive to improve the stability of the prepared samples. The result provided an approach to get CsPbI₃ perovskite nanocrystals with stabile PL. Finally, CsPbI₃ NPLs embedded in the polystyrene film displayed bright and stable white light emission. [ABSTRACT FROM AUTHOR]