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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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Exciton-phonon coupling in two-dimensional layered (BA)2PbI4 perovskite microplates
Yixiong Wang1, Chenglin He2, Qin Tan2
1School of Physics and Electronics, Hunan University Changsha Hunan 410082 China.
RSC Advances
|February 23, 2023
Summary
Exciton-phonon interaction significantly impacts the optoelectronic properties of (BA)2PbI4 perovskites. Stronger interactions in surface emissions cause spectral broadening and red-shifts with increasing temperature.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Optoelectronics
Background:
- Two-dimensional layered perovskites, specifically (BA)2PbI4, are promising for optoelectronic devices.
- Understanding exciton-phonon interactions is crucial for optimizing their performance.
Purpose of the Study:
- To investigate the influence of exciton-phonon coupling on the optoelectronic properties of (BA)2PbI4 microplates.
- To correlate exciton-phonon coupling with the length of organic carbon chain ligands.
Main Methods:
- Synthesis of high-quality (BA)2PbI4 microplates via solution methods.
- Detection of dual-excitonic emission peaks (surface and interior) at low temperatures.
- Determination of phonon mode energies and exciton-phonon coupling strengths.
Main Results:
- Dual-excitonic emission peaks were observed in (BA)2PbI4 microplates.
- Exciton-phonon coupling strengths were determined for surface and interior emissions.
- Stronger exciton-phonon interaction in surface emissions led to spectral broadening and red-shift with increasing temperature.
- (OA)2PbI4 microplates with longer ligands showed a single emission peak and strong coupling.
Conclusions:
- Exciton-phonon coupling significantly influences the excitonic emission in (BA)2PbI4.
- A direct relationship exists between exciton-phonon coupling and the length of organic ligands.
- This study provides insights for designing advanced layered perovskite materials for optoelectronics.
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