Polarized Optoelectronics of CsPbX3 (X = Cl, Br, I) Perovskite Nanoplates with Tunable Size and Thickness

Low dimensional semiconductor nanomaterials have shown their tailorable properties for a variety of promising applications in decades. Here a general strategy to synthesize all-inorganic CsPbX3 (X = Cl, Br, I or their mixture) perovskite 2D nanoplates by introducing additional metal halides MX'(2) or MX'(3) (M = Cu, Zn, Al or Pb, etc.; X' = Cl, Br or I) is reported. These CsPbX3 perovskite nanoplates have uniform thickness and tunable size, which can be feasibly controlled by the component and ratio of the metal halides, temperature, time, and ligands. The well-defined morphology of the nanoplates makes them ideal building blocks for the self-assembly in the face-to-face and column-by-column arrangement. Compared to the optically isotropic CsPbX3 nanocubes, the 2D CsPbX3 nanoplates exhibit remarkable polarized UV-vis absorption and photoluminescence not only in liquid solvent and solid resin matrix, but also in self-assembled films. An optoelectronic photodetector sensitive for linear polarized light is fabricated to demonstrate the proof-of-concept.