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Updated: Sep 27, 2025
04:14
Facile Synthesis of Colloidal Lead Halide Perovskite Nanoplatelets via Ligand-Assisted Reprecipitation
Published on: October 1, 2019
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Structural Diversity in Multicomponent Nanocrystal Superlattices Comprising Lead Halide Perovskite Nanocubes
Ihor Cherniukh1, Taras V Sekh1, Gabriele Rainò1
1Institute of Inorganic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, CH-8093 Zürich, Switzerland.
ACS Nano
|April 6, 2022
Summary
This study demonstrates diverse superlattice structures using shape-anisotropic nanocrystals, enabling new materials engineering possibilities. These ordered nanocrystal assemblies exhibit unique electronic properties at low temperatures.
Area of Science:
- Materials Science
- Nanotechnology
- Solid State Physics
Background:
- Nanocrystal (NC) self-assembly is crucial for mesoscale materials engineering.
- Shape anisotropy in NCs enables unique structural outcomes compared to spherical NCs.
Purpose of the Study:
- To explore structural diversity in multicomponent superlattices (SLs) using luminescent cubic CsPbBr3 NCs.
- To investigate coassembly with various NC shapes (spheres, truncated cuboids, disks).
- To develop substrate-free methods for SL formation.
Main Methods:
- Coassembly of CsPbBr3 (or FAPbBr3) NCs with spherical, truncated cuboid, and disk-shaped NCs.
- Formation of binary SLs with high packing density.
- Implementation of oil-in-oil templated assembly and liquid-air interface assembly for substrate-free SLs.
Main Results:
- Achieved six types of binary SLs (AB2, quasi-ternary ABO3, ABO6, NaCl, AlB2, CuAu) with high packing density.
- Observed orientational coherence of nanocubes within SLs.
- Formed orthorhombic SLs resembling CaC2 structure using nanocubes and nanodisks.
- Demonstrated substrate-free formation of supraparticles and thin films.
- Observed collective electronic states with red-shifted photoluminescence and absorption bands at low temperatures.
Conclusions:
- Diverse, long-range ordered superlattices can be formed by coassembling shape-anisotropic NCs.
- Substrate-free methods offer new pathways for SL fabrication.
- Dense NC packing leads to emergent electronic properties at low temperatures.
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