Intermediate-Site Anchoring Ligands Enable Robust Nonlayered Interfacial Passivation for Efficient and Stable...

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Air-processed perovskite solar cells face challenges with moisture and oxygen, requiring robust surface passivation.
• Conventional ammonium ligand passivation can lead to intercalation, increased resistance, and reduced stability.

Purpose of the Study:

• To develop a novel ligand-based passivation strategy for improved air-processed perovskite solar cells.
• To enhance interfacial properties and environmental stability using intermediate-site anchoring.

Main Methods:

• Utilized a series of choline derivatives for nonlayered interfacial passivation.
• Employed thioacyl sulfur for strong coordination with Pb2+ sites and iodide for halide vacancy healing.
• Formed a thermally robust and electronically homogeneous top interface.

Main Results:

• Achieved a record power conversion efficiency (PCE) of 26.54% for air-processed n-i-p perovskite solar cells.
• Demonstrated excellent operational stability, retaining over 90% PCE after 2000 hours at 65°C and 1000 hours of continuous tracking.
• Projected T80 lifetimes of ~9800 hours (illumination) and ~11000 hours (thermal aging).

Conclusions:

• The intermediate-site anchoring strategy offers superior surface passivation compared to conventional methods.
• This approach significantly enhances both efficiency and long-term stability of air-processed perovskite solar cells.
• The developed passivation technique is promising for scalable fabrication of stable perovskite solar cells.