Lead Derivative-Based Precursor Engineering Enables Halogen-Uniform Perovskite Solar Cells with Enhanced Stability...

Area of Science:

• Materials Science
• Renewable Energy

Background:

• Perovskite solar cells (PSCs) offer excellent opto-electrical properties and solution-processability.
• Achieving high PSC efficiency requires precise bandgap control, often using mixed halide compositions.
• Mixed halides can lead to phase segregation, reducing efficiency and stability.

Purpose of the Study:

• To develop a precursor method for preparing halide-uniform perovskites.
• To investigate the impact of halide uniformity on PSC performance and stability.
• To enhance the efficiency and durability of wide-bandgap mixed halide perovskites.

Main Methods:

• A novel precursor approach using lead derivatives (nPbI2:1PbXA) was employed.
• This method tunes bonding to create stable halide fragments, preventing segregation.
• The approach was applied to CsPbI2.8Br0.2 and Cs0.2FA0.8I1.9Br1.1 perovskite compositions.

Main Results:

• The precursor method successfully minimized halide segregation in perovskites.
• Achieved power conversion efficiencies of 21.3% and 20.3% for specific compositions.
• Demonstrated a correlation between halide uniformity and improved mechanical tolerance.
• Solar cells retained over 90% efficiency after 1500 hours of continuous operation.

Conclusions:

• The developed precursor method is effective for creating stable, halide-uniform perovskites.
• Enhanced halide homogeneity boosts PSC efficiency, mechanical robustness, and long-term stability.
• This approach offers a promising route for advancing high-performance perovskite solar cell technology.