Homoepitaxial Seed-Mediated Growth for High-Efficiency FAPbI₃ Perovskite Solar Cells

Area of Science:

• Materials Science
• Renewable Energy
• Nanotechnology

Background:

• Seed-mediated growth is key for high-efficiency perovskite solar cells (PSCs).
• High-quality perovskite nanocrystals (PNCs) are crucial seeds for homogenous growth.
• The poor stability of iodine-based perovskite PNCs limits their use as seeds.

Purpose of the Study:

• To enhance the stability and optical properties of FAPbI3 and CsPbI3 PNCs using cyclohexylamine (CA).
• To enable the use of these stabilized PNCs as seeds for fabricating high-quality FAPbI3 perovskite films.
• To improve the power conversion efficiency (PCE) and stability of PSCs.

Main Methods:

• Incorporation of cyclohexylamine (CA) molecules into FAPbI3 and CsPbI3 PNCs.
• Utilizing FAPbI3 PNCs as seeds for homogeneous, lattice-matched growth of FAPbI3 perovskite films.
• Fabrication and characterization of PSCs using the enhanced PNC seeds.

Main Results:

• Enhanced stability and optical properties of CA-modified FAPbI3 and CsPbI3 PNCs.
• Fabrication of high-quality FAPbI3 perovskite films with larger grain sizes and reduced defect densities.
• Increased PSC power conversion efficiency (PCE) from 22.35% to 25.55%.
• Improved PSC stability, retaining 92.4% efficiency after 3 months of ambient storage.

Conclusions:

• Cyclohexylamine (CA) modification effectively enhances the stability of perovskite nanocrystals (PNCs).
• Homogeneous seed-mediated growth using stabilized PNCs leads to high-quality perovskite films and efficient PSCs.
• This strategy offers a promising route for developing stable and high-performance perovskite solar cells.