2D Perovskite Engineering Enables Robust Self-Assembled Monolayers for High-Performance Perovskite Solar Cells

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Self-assembled monolayers (SAMs) are crucial for hole-selective contacts in perovskite solar cells (PSCs).
• Existing SAMs face degradation and aggregation issues during solution-based perovskite deposition, limiting device performance and scalability.
• Developing robust interfaces is key for efficient and stable PSCs.

Purpose of the Study:

• To introduce a transient 2D perovskite protection strategy to safeguard SAMs during PSC fabrication.
• To improve the uniformity of large-area perovskite films and enhance charge extraction.
• To demonstrate the scalability and operational stability of PSCs using this protection method.

Main Methods:

• Utilized a volatile propylammonium chloride additive to form a transient 2D perovskite layer.
• This layer temporarily protected SAMs from solvent-induced degradation during perovskite deposition.
• The protective layer was designed to decouple during thermal annealing, preserving the SAM interface.

Main Results:

• Achieved a power conversion efficiency (PCE) of 26.14% for small-area (0.05 cm²) PSCs.
• Demonstrated scalable efficiencies of 23.27% for a 5 × 5 cm² mini-module and 22.34% for a 30 × 30 cm² module (615.7 cm² active area).
• The large-area module maintained 90% of its initial efficiency after 2000 hours of continuous operation, indicating high stability.

Conclusions:

• The transient 2D perovskite protection strategy effectively preserves SAM integrity and promotes uniform perovskite crystallization.
• This approach enables high-performance, stable, and scalable perovskite solar cells.
• Highlights a viable pathway for the reliable commercialization of perovskite photovoltaics.