Homogenizing out-of-plane strain distribution for high-performance flexible perovskite photovoltaics

Area of Science:

• Materials Science
• Renewable Energy
• Solid-State Physics

Background:

• Flexible perovskite solar cells (PVSCs) offer lightweight and adaptable photovoltaic solutions.
• Challenges include nonuniform strain and residual stress, hindering stability and mechanical robustness.

Purpose of the Study:

• To improve the stability and mechanical properties of flexible perovskite solar cells.
• To achieve high power conversion efficiencies and long-term operational durability.

Main Methods:

• Optimized A-site doping to reduce defect density and microstrain.
• Advanced visualization techniques for out-of-plane strain analysis.
• In-situ formation of a 2D perovskite layer on PbI2-rich surfaces.

Main Results:

• Achieved champion power conversion efficiencies of 26.59% (rigid) and 25.88% (flexible).
• Demonstrated high efficiencies for large-area flexible modules (21.77% for 25 cm², 19.23% for 100 cm²).
• Unencapsulated flexible devices retained 97.8% efficiency after 2000 hours under ISOS-L-1 testing.

Conclusions:

• Optimized doping and 2D passivation strategies significantly enhance PVSC performance and durability.
• The findings provide a foundation for the commercialization of flexible perovskite solar technology.