Interfacial Rivet to Fill Structural Defects: A Spacer Engineering Gift for 3D Solar Cells

Area of Science:

• Materials Science
• Photovoltaics
• Nanotechnology

Background:

• Perovskite solar cells (PSCs) show promise but are limited by defects at surfaces and interfaces.
• Achieving high-quality perovskite films by combining 2D and 3D materials is challenging due to complex surface reactions.

Purpose of the Study:

• To develop a method for precisely controlling 2D perovskite structures on 3D perovskite films.
• To enhance the efficiency and stability of perovskite solar cells through interface engineering.

Main Methods:

• Synthesized phase-pure 2D (HA)2(MA)n-1PbnI3n+1 perovskites with controlled layer numbers (n).
• Utilized these 2D perovskites as interface rivets to optimize 3D perovskite films, tuning defects and grain boundaries.
• Fabricated and characterized perovskite solar cells using the optimized film system.

Main Results:

• Reduced non-radiative recombination, leading to improved optical performance, higher carrier mobility, and lower trap density.
• Achieved a champion power conversion efficiency (PCE) over 25% with enhanced open-circuit voltage (VOC) and fill factor (FF).
• Demonstrated large-area device uniformity and PCE over 21.24% on a 14 cm2 active area.

Conclusions:

• The 2D perovskite interface rivet strategy effectively optimizes 3D perovskite films for high-performance solar cells.
• This approach offers a new pathway for enhancing the efficiency and long-term stability of perovskite solar cells.
• The scalable synthesis and application of 2D perovskites present a promising direction for next-generation photovoltaics.