Competitive-binding buried interlayer for year-round reproducible perovskite solar cells

Area of Science:

• Materials Science
• Photovoltaics
• Chemical Engineering

Background:

• Posttreatment homogenization of perovskite solar cell surfaces is advanced.
• Imperfections at the buried interface are difficult to remedy after film generation.

Purpose of the Study:

• To address defects like residual lead iodide and voids at the buried interface.
• To improve perovskite solar cell performance and stability.

Main Methods:

• Introduced a potassium dihydrogen phosphate competitive-binding interlayer.
• Utilized strong chemical interactions to reduce residual solvents at the buried interface.

Main Results:

• Achieved a homogenized buried interface, enhancing perovskite film quality and charge extraction.
• Resulted in year-round improvements in photovoltaic performance and reproducibility.
• Achieved a champion power conversion efficiency (PCE) of 26.3% and maintained 97% of initial PCE after 1000 hours.

Conclusions:

• The potassium dihydrogen phosphate interlayer effectively resolves buried interface issues in perovskite solar cells.
• This approach leads to significant enhancements in device efficiency and long-term stability.