Bidirectional Chemo-Mechanical Interface Stabilization in Perovskite Solar Cells

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Perovskite solar cells (PSCs) face challenges with interfacial instability, including chemical aggregation and mechanical delamination.
• These issues degrade long-term performance and hinder commercial application of PSCs.

Purpose of the Study:

• To introduce a molecular-level stabilization strategy for the perovskite/C60 interface in PSCs.
• To address the concurrent lateral and vertical degradation pathways at the interface.

Main Methods:

• Incorporation of an ultrathin 1,3,6,8-pyrenetetrasulfonic tetrasodium salt (PTS) interfacial layer.
• Utilizing PTS's sulfonate groups for perovskite anchoring and pyrene cores for π-π interactions with C60.
• Investigating the bidirectional chemo-mechanical interface stabilization (BCIS) mechanism.

Main Results:

• Achieved power conversion efficiencies (PCEs) up to 26.53% in PSCs.
• Demonstrated remarkable stability: 96% PCE retention after 1,000 h and 91% after 300 thermal cycles.
• Successfully scaled PTS treatment to large-area (818 cm2) perovskite solar modules (PSMs) with PCEs over 20% under industrial conditions.

Conclusions:

• Bidirectional interface engineering using PTS is a highly effective strategy for stabilizing PSCs.
• The BCIS mechanism significantly improves device longevity and performance.
• This approach is crucial for advancing commercially viable perovskite photovoltaics.