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Updated: Jun 4, 2025
08:12
Low Pressure Vapor-assisted Solution Process for Tunable Band Gap Pinhole-free Methylammonium Lead Halide Perovskite Films
Published on: September 8, 2017
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Methylammonium Lead Iodide across Physical Space: Phase Boundaries and Structural Collapse.
Pelayo Marin-Villa1, Mattia Gaboardi1,2, Boby Joseph3
1Materials Physics Center, CSIC-UPV/EHU, Paseo de Manuel Lardizabal, 5, 20018 Donostia - San Sebastian, Spain.
The Journal of Physical Chemistry Letters
|December 23, 2024
Summary
Researchers mapped the pressure-temperature phase diagram of methylammonium lead iodide (MAPbI3) hybrid perovskites. High-pressure octahedral distortions were found to drive structural collapse and amorphization, impacting material stability.
Area of Science:
- Materials Science
- Solid-State Physics
- Crystallography
Background:
- Hybrid perovskites, like methylammonium lead iodide (MAPbI3), have complex structures and phase behaviors crucial for stability.
- Understanding these properties under varying conditions is key to optimizing their performance.
Purpose of the Study:
- To comprehensively investigate the pressure-temperature phase diagram of methylammonium lead iodide (MAPbI3).
- To elucidate the atomic and molecular mechanisms driving structural phase transitions in MAPbI3.
Main Methods:
- Combined neutron and synchrotron diffraction experiments across a wide range of pressures and temperatures.
- Ab initio molecular dynamics simulations, validated by experimental data.
Main Results:
- Detailed mapping of the MAPbI3 pressure-temperature phase diagram.
- Identification of negative thermal expansion near phase boundaries.
- Observation of pronounced octahedral distortions at high pressures leading to amorphization.
Conclusions:
- Structural phase transitions in MAPbI3 are driven by octahedral distortions under pressure.
- High-pressure-induced distortions lead to structural collapse and amorphization, affecting material stability.
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