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Facile Synthesis of Colloidal Lead Halide Perovskite Nanoplatelets via Ligand-Assisted Reprecipitation
Published on: October 1, 2019
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Control over Banded Morphologies and Circular Dichroism in Chiral Halide Perovskites
Matthew P Hautzinger1, Qiutong Ge1, Md Azimul Haque1
1National Renewable Energy Laboratory, Golden, Colorado 80401, United States.
ACS Nano
|May 15, 2025
Summary
Chiral halide perovskites exhibit tunable chiroptoelectronic properties. Controlling their banded morphology impacts circular dichroism, enabling potential applications in light polarization control.
Area of Science:
- Materials Science
- Solid-State Physics
- Optoelectronics
Background:
- Chiral halide perovskites (c-HPs) combine organic chirality with inorganic semiconductor properties.
- These materials offer tunable chiroptoelectronic behavior for advanced applications.
- Understanding morphology-property relationships is crucial for material design.
Purpose of the Study:
- Investigate the impact of periodic banded morphologies in textured chiral halide perovskite films on their chiroptical behavior.
- Explore the relationship between film growth conditions, morphology, and circular dichroism (CD) spectra.
- Develop a model to explain and predict CD spectral features based on morphological characteristics.
Main Methods:
- Fabrication of textured chiral halide perovskite (R/S-NEA)2PbBr4 films with controlled banded morphologies.
- Characterization of film morphology, including radial banding and crystallite orientation, as a function of growth temperature.
- Measurement and analysis of circular dichroism (CD) spectra across various processing conditions.
- Development of a theoretical model incorporating optical effects like refraction and birefringence to explain observed CD spectra.
Main Results:
- Rhythmic precipitation driven by crystalline-glassy phase interplay leads to controllable radial banded morphologies.
- Growth temperature influences the spacing and density of these banded regions.
- CD spectral shape, intensity, and polarity are linked to morphological features such as surface refraction, birefringence, and stacked crystallites.
- The developed model accurately reproduces observed CD spectra, explaining variations attributed to morphology.
Conclusions:
- Control over chiral halide perovskite film morphology, specifically banded patterns, directly influences chiroptical properties.
- The interplay of optical phenomena arising from morphology is key to understanding CD spectra.
- This work provides a predictive model for CD behavior and highlights the potential for exploiting structural features for light polarization control, similar to metamaterials.
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