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.