Related Experiment Video
Updated: Jun 19, 2026
11:38
Influence of Hybrid Perovskite Fabrication Methods on Film Formation, Electronic Structure, and Solar Cell Performance
Published on: February 27, 2017
Phase Homogeneity and Photothermal Stability in Fully Vacuum-Processed Perovskite Solar Cells
Isabella Poli1, Michele Sessolo2, Daniele Meggiolaro3
1Center for Sustainable Future Technologies, Istituto Italiano di Tecnologia, via Livorno 60, Torino 10144, Italy.
ACS Energy Letters
|June 18, 2026
Summary
Vacuum-deposited perovskite solar cells show excellent thermal stability. However, light exposure revealed degradation in Cs-containing films, while MA-containing and mixed halide films demonstrated long-term operational stability, highlighting crystallization
Area of Science:
- Materials Science
- Renewable Energy
- Photovoltaics
Background:
- Solvent-free fabrication of perovskite thin films via vacuum deposition enhances long-term stability by avoiding residual solvents.
- Mixed-cation perovskites are crucial for advancing photovoltaic performance and durability.
- Understanding degradation mechanisms under thermal and light stress is essential for developing stable perovskite solar cells.
Purpose of the Study:
- To investigate the thermal and light stability of vacuum-deposited mixed-cation perovskite compositions: FA0.8Cs0.2PbI3 and FA0.8MA0.2PbI3.
- To identify degradation pathways and factors influencing stability under operational stress.
- To evaluate the long-term operational stability of perovskite solar cells fabricated with promising compositions.
Main Methods:
- Thermal evaporation of mixed-cation perovskite thin films (FA0.8Cs0.2PbI3 and FA0.8MA0.2PbI3).
- Exposure to thermal stress (85 °C for 500 h) and light stress (continuous illumination).
- Characterization of structural, optical, and morphological properties.
- Fabrication and testing of perovskite solar cells under outdoor and indoor illumination conditions.
Main Results:
- Both compositions exhibited excellent thermal stability, retaining properties after 500 h at 85 °C.
- FA0.8Cs0.2PbI3 showed significant degradation under light due to CsI-rich segregations and associated defects.
- Partial bromide substitution (FA0.8Cs0.2Pb-(I0.8Br0.2)3) improved film homogeneity and light stability.
- Perovskite solar cells using FA0.8MA0.2PbI3 and FA0.8Cs0.2Pb-(I0.8Br0.2)3 maintained performance for four months outdoors and 900 h indoors.
Conclusions:
- Vacuum-deposited mixed-cation perovskites, particularly those containing methylammonium (MA+), offer potential for long-lived perovskite photovoltaics.
- High-quality crystallization processes are key to mitigating degradation pathways and achieving operational stability.
- Careful compositional engineering, including halide mixing, can further enhance the stability of perovskite solar cells.
