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Updated: Jul 1, 2025
Facile Synthesis of Colloidal Lead Halide Perovskite Nanoplatelets via Ligand-Assisted Reprecipitation
Published on: October 1, 2019
A-Site Cation Influence on the Structural and Optical Evolution of Ultrathin Lead Halide Perovskite Nanoplatelets
Chantalle J Krajewska1, Matthias Kick1, Alexander E K Kaplan1
1Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
Abstract:
Imposing quantum confinement has the potential to significantly modulate both the structural and optical parameters of interest in many material systems. In this work, we investigate strongly confined ultrathin perovskite nanoplatelets APbBr3. We compare the all-inorganic and hybrid compositions with the A-sites cesium and formamidinium, respectively. Compared to each other and their bulk counterparts, the materials show significant differences in variable-temperature structural and optical evolution. We quantify and correlate structural asymmetry with the excitonic transition energy, spectral purity, and emission rate. Negative thermal expansion, structural and photoluminescence asymmetry, photoluminescence full width at half-maximum, and splitting between bright and dark excitonic levels are found to be reduced in the hybrid composition. This work provides composition- and structure-based mechanisms for engineering of the excitons in these materials.
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