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Updated: Aug 14, 2025
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Influence of Hybrid Perovskite Fabrication Methods on Film Formation, Electronic Structure, and Solar Cell Performance
Published on: February 27, 2017
18.6K
Elucidating Polaron Dynamics in Cs2AgBiBr6 Double Perovskite
Naveen Kumar Tailor1, Saurabh K Saini2, Pankaj Yadav3
1Department of Physics, Indian Institute of Technology Roorkee, Roorkee, Haridwar, Uttarakhand247667, India.
The Journal of Physical Chemistry Letters
|January 17, 2023
Summary
Lead-free Cs2AgBiBr6 perovskites show promise for optoelectronics, but their performance is limited by small polaron formation. This study reveals polaron localization and hopping as key factors affecting carrier dynamics in these materials.
Area of Science:
- Materials Science
- Solid-State Physics
- Photovoltaics
Background:
- Lead-free Cs2AgBiBr6 double perovskites are emerging alternatives to lead-based materials for optoelectronic devices.
- Research has focused on device engineering, with less attention on intrinsic photophysical properties.
Purpose of the Study:
- To investigate the intrinsic photophysical properties limiting carrier dynamics in Cs2AgBiBr6.
- To understand the role of polaron formation and localization in Cs2AgBiBr6 performance.
Main Methods:
- Ultrafast transient absorption spectroscopy to study photoexcitation effects.
- Temperature-dependent AC conductivity measurements to analyze conduction mechanisms.
Main Results:
- Small polaron formation and localization under photoexcitation limit carrier dynamics.
- Single polaron hopping is identified as the dominant conduction mechanism.
- Photoexcitation induces lattice deformation, forming self-trapped states (STSs) that rapidly trap charge carriers.
Conclusions:
- Small polarons and their localization are intrinsic limitations in Cs2AgBiBr6 double perovskites.
- Understanding these properties is crucial for optimizing Cs2AgBiBr6 and other bismuth-based semiconductors.
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