Related Experiment Video
Updated: May 16, 2026
08:12
Low Pressure Vapor-assisted Solution Process for Tunable Band Gap Pinhole-free Methylammonium Lead Halide Perovskite Films
Published on: September 8, 2017
An entropy-regulating molecular lock stabilizes formamidinium lead halide perovskite
Tianyin Miao1,2, Sanwan Liu3, Xia Lei4,5
1Wuhan National Laboratory for Optoelectronics (WNLO) and School of Optical and Electronic Information, Huazhong University of Science and Technology (HUST), Wuhan, China.
Science (New York, N.Y.)
|May 14, 2026
Summary
Researchers developed a molecular-lock strategy using 3-PMPCl to stabilize formamidinium lead iodide (FAPbI3) perovskite solar cells (PSCs). This enhanced stability, combined with a bismuth electrode, achieved long-term operational performance, crucial for advancing solar energy technology.
Area of Science:
- Materials Science
- Renewable Energy
Background:
- Formamidinium lead iodide (FAPbI3) perovskite solar cells (PSCs) face instability issues due to the Pb-I lattice structure.
- The hexagonal δ-phase is thermodynamically unfavorable under operating conditions, limiting device longevity.
Purpose of the Study:
- To enhance the operational stability of FAPbI3-based PSCs.
- To investigate an entropy-regulating molecular-lock strategy for stabilizing the α-phase of perovskites.
Main Methods:
- Utilized 1-pyridin-3-ylmethyl-piperazine hydrochloride (3-PMPCl) as a molecular-lock additive.
- Investigated the interactions between 3-PMPCl and the perovskite lattice to modulate cation rotational freedom and suppress entropy increase.
- Employed a stable bismuth electrode in conjunction with the stabilized perovskite.
Main Results:
- Achieved a certified power conversion efficiency (PCE) of 27.6% in FAPbI3-based PSCs.
- Demonstrated enhanced phase stability of the α-phase under elevated temperature and humidity.
- Developed a device retaining 93.0% of its initial PCE (26.8%) after 1011 hours at 85°C under 1-sun illumination using a bismuth electrode.
Conclusions:
- The entropy-regulating molecular-lock strategy effectively stabilizes the FAPbI3 perovskite structure.
- Combining this stabilization with a bismuth electrode significantly improves the operational stability of PSCs.
- This approach offers a promising pathway for developing durable and efficient perovskite solar cells.
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