Vacuum-Evaporated Perovskite and Interfacial Modifier for Efficient Perovskite Solar Cells

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Surface passivation is critical for high-performance perovskite solar cells (PSCs).
• Vacuum evaporation offers a scalable, solvent-free method for depositing uniform thin films.
• Evaporation of organic additives for perovskite surface passivation remains underexplored.

Purpose of the Study:

• To introduce a vacuum evaporation method for depositing a novel organic salt, 2-chlorophenethylamine pentafluorobenzene sulfonate (2-ClPEAPf), for perovskite surface passivation.
• To investigate the effectiveness of 2-ClPEAPf in passivating interfacial defects and preventing moisture ingress.
• To evaluate the impact of this passivation strategy on the photovoltaic performance and operational stability of PSCs.

Main Methods:

• Developed a vacuum evaporation technique to deposit 2-ClPEAPf onto perovskite layers.
• Fabricated planar n-i-p perovskite solar cells using the treated perovskite films.
• Characterized the photovoltaic performance (PCE) and operational stability under continuous light irradiation.

Main Results:

• Achieved a maximum power conversion efficiency (PCE) of 25.16% for 0.1 cm² devices.
• Obtained a certified PCE of 24.00% for 1.0 cm² devices.
• Demonstrated enhanced operational stability, retaining 92.5% of initial efficiency after 800 hours for 0.1 cm² devices.

Conclusions:

• Vacuum-evaporated 2-ClPEAPf effectively passivates perovskite surfaces, reducing defects and improving moisture resistance.
• This method significantly enhances both the power conversion efficiency and operational stability of perovskite solar cells.
• The findings present a promising scalable approach for fabricating high-performance and durable perovskite solar cells.