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Updated: Jun 23, 2026
10:42
Combining Solid-state and Solution-based Techniques: Synthesis and Reactivity of Chalcogenidoplumbates(II or IV)
Published on: December 29, 2016
Overcoming Charge-Carrier Localization in Metal Chalcohalides
Bembe C Mackintosh1, Marcello Righetto1,2, G Krishnamurthy Grandhi3
1Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom.
Journal of the American Chemical Society
|June 22, 2026
Summary
Researchers overcame charge-carrier localization in perovskite-inspired materials (PIMs) by chemically tuning metal chalcohalides. This enhances their potential as efficient, lead-free solar absorbers for next-generation solar cells.
Area of Science:
- Materials Science
- Solid-State Physics
- Photovoltaics
Background:
- Effective charge-carrier transport is crucial for advanced thin-film solar cells.
- Perovskite-inspired materials (PIMs), such as metal chalcohalides, are promising lead-free solar absorbers.
- Charge-carrier localization hinders transport properties in many PIMs.
Purpose of the Study:
- To understand and overcome charge-carrier localization in metal chalcohalides.
- To explore chemical substitution strategies for improving PIMs.
- To establish structure-property relationships for enhanced solar energy harvesting.
Main Methods:
- Synthesized and characterized mixed-metal chalcohalides (A2BCh2X3) with varying A-site cations.
- Investigated lattice symmetry changes (e.g., monoclinic P21/c to orthorhombic Cmcm).
- Measured charge-carrier dynamics using time-resolved photoconductivity measurements.
Main Results:
- Chemical substitution shifted lattice symmetry from monoclinic P21/c (Pb2SbS2I3) to orthorhombic Cmcm (Sn2SbS2I3).
- Pb2SbS2I3 exhibited rapid charge-carrier localization (picoseconds).
- Sn2SbS2I3 demonstrated suppressed localization and longer-lived nanosecond photoconductivity.
Conclusions:
- Higher lattice symmetry and electronic dimensionality in Sn2SbS2I3 suppress charge-carrier localization.
- Facile chemical tuning of metal chalcohalides can overcome localization issues.
- This work provides a pathway for developing efficient PIM absorbers for solar cells.
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