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Low Pressure Vapor-assisted Solution Process for Tunable Band Gap Pinhole-free Methylammonium Lead Halide Perovskite Films
Published on: September 8, 2017
Engineering halide composition to control structural and electronic properties in bismuth-based perovskite-inspired
Michael Zambrano-Angulo1, Adriana Pecoraro1, Roberto Grisorio2
1Department of Physics "E. Pancini", University of Naples Federico II, Naples, 80126, Italy. anabelen.munozgarcia@unina.it.
Physical Chemistry Chemical Physics : PCCP
|June 16, 2026
Summary
Lead-free bismuth perovskites offer a safer alternative for optoelectronic devices. Halogen composition critically impacts their structural, electronic, and transport properties, guiding future material design.
Area of Science:
- Materials Science
- Solid-State Physics
- Photovoltaics
Background:
- Lead halide perovskites are leading optoelectronic materials but raise toxicity concerns due to lead.
- Bismuth-based perovskite-inspired materials offer a promising lead-free alternative with tunable properties.
Purpose of the Study:
- Investigate the structural, electronic, and transport properties of Cs3Bi2I9 and Cs3Bi2Br9.
- Explore the effects of iodine/bromine (I/Br) mixing on these properties.
- Provide insights for optimizing halide content in perovskite-inspired materials.
Main Methods:
- State-of-the-art first-principles calculations.
- Analysis of phase stability, electronic bandgap, and effective masses.
- Investigation of charge carrier mobility and localization.
Main Results:
- Phase stability shifts with Br content, favoring different crystal structures (P63/mmc vs. P-3m1).
- Electronic bandgap increases with higher bromine content.
- Electrons show higher mobility than holes, which become more localized with increasing Br.
Conclusions:
- Halogen composition is crucial for tuning the properties of bismuth perovskite-inspired materials.
- These findings are valuable for designing efficient lead-free materials for photovoltaics and photocatalysis.
- Optimizing halide ratios is key for next-generation optoelectronic applications.
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