Colloidal Synthesis of CH₃NH₃PbBr₃ Nanoplatelets with Polarized Emission through Self‐Organization

Abstract

We report a combined experimental and theoretical study of the synthesis of CH NH PbBr nanoplatelets through self-organization. Shape transformation from spherical nanodots to square or rectangular nanoplatelets can be achieved by keeping the preformed colloidal nanocrystals at a high concentration (3.5 mg mL ) for 3 days, or combining the synthesis of nanodots with self-organization. The average thickness of the resulting CH NH PbBr nanoplatelets is similar to the size of the original nanoparticles, and we also noticed several nanoplatelets with circular or square holes, suggesting that the shape transformation experienced a self-organization process through dipole-dipole interactions along with a realignment of dipolar vectors. Additionally, the CH NH PbBr nanoplatelets exhibit excellent polarized emissions for stretched CH NH PbBr nanoplatelets embedded in a polymer composite film, showing advantageous photoluminescence properties for display backlights.

Two-Dimensional Halide Perovskites for Emerging New- Generation Photodetectors

“…(d) The procedure for preparing CH 3 NH 3 PbI 3 plates on a patterned substrate [52]. (e) Self-transformation of CH 3 NH 3 PbBr 3 nanodots to nanoplatelets [53]. The enlarged parts represent the corresponding TEM images of CH 3 NH 3 PbBr 3 nanocrystals.…”

“…Liu et al demonstrated the self-organization process for the transformation of CH 3 NH 3 PbBr 3 nanodots (NDs) to NPLs [53]. In detail, the CH 3 NH 3 PbBr 3 NDs were dissolved in a nonpolar solvent and aged in darkness (Figure 3e).…”

“…The resulting NPLs loaded into a polymer matrix (4-methyl-1-pentene, TPX) displayed cos/sin intensity dependence on the polarizer angles for the PL emission. In addition, this method offers a new way for controlling the shape of perovskite-based nanomaterials with polarized emission [53]. Jodlowski et al reported the preparation of a bi-dimensional (i.e.…”

“…(d) Band gaps from experiment and SR-, SOC-DFT calculations [70]. (e) Simulations of total potential field in a four-dot alignment [53]. (f) DOS curves of the neutral lead vacancy and isodensity plot of the defect states in (EDBE)PbI 4 [73].…”

Lead Halide Perovskite Nanocrystals: Stability, Surface Passivation, and Structural Control

“…Likewise, Liu et al. synthesized uniform and luminescent CH 3 NH 3 PbBr 3 nanoplatelets through self‐organization of preformed colloidal CH 3 NH 3 PbBr 3 nanodots based on dipole–dipole interactions …”