High-efficiency two-dimensional Ruddlesden-Popper perovskite solar cells

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Three-dimensional (3D) organic-inorganic perovskites offer high power conversion efficiencies (>20%) for thin-film solar cells.
• However, 3D perovskites suffer from poor environmental and photostability.
• Layered 2D perovskites (Ruddlesden-Popper phases) show improved stability but limited efficiency (4.73%) due to inhibited charge transport.

Purpose of the Study:

• To enhance the efficiency and stability of 2D perovskite solar cells.
• To overcome the charge transport limitations in layered perovskite structures.
• To develop a pathway for high-performance, stable optoelectronic devices.

Main Methods:

• Fabrication of near-single-crystalline 2D perovskite thin films.
• Achieving preferential out-of-plane alignment of inorganic perovskite crystallographic planes.
• Fabrication of planar solar cells using these aligned films.

Main Results:

• Achieved a photovoltaic efficiency of 12.52% with no hysteresis.
• Demonstrated significantly improved stability under light, humidity, and heat stress compared to 3D perovskites.
• Unencapsulated devices retained >60% efficiency for over 2,250 hours under illumination.
• Encapsulated devices showed no degradation under illumination or humidity.

Conclusions:

• Solution-processed, single-crystalline 2D perovskite thin films enable efficient charge transport.
• These layered perovskites offer a promising route to high-performance optoelectronic devices with long-term stability.
• The findings pave the way for technologically relevant, stable perovskite-based solar cells.