Lewis Acid-Base Coordination-Driven Interface Passivation Using 3-Hydroxyflavone for Inverted Perovskite Solar Cells.

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Perovskite solar cells face challenges with interface recombination and instability under illumination, hindering commercialization.
• Developing effective passivation strategies is crucial for enhancing device performance and longevity.

Purpose of the Study:

• To develop and evaluate an interfacial passivation strategy using 3-hydroxyflavone (3-HF) for perovskite solar cells.
• To address interface recombination and improve long-term stability for scalable applications.

Main Methods:

• Utilized 3-hydroxyflavone (3-HF) for interfacial passivation via Lewis acid-base coordination with Pb²⁺.
• Investigated the formation of stable structures to suppress interface defects and increase ion-migration barriers.
• Optimized energy-level alignment at the interface for enhanced charge extraction and transport.

Main Results:

• Achieved a champion power conversion efficiency (PCE) of 26.6% in small-area (0.09 cm²) perovskite solar cells.
• Demonstrated enhanced performance and stability in 14 cm² mini-modules, reaching a PCE of 22.6%.
• Mini-modules maintained 98.9% of initial performance after 500 hours of continuous illumination.

Conclusions:

• 3-HF passivation effectively suppresses interface defects and enhances ion-migration barriers in perovskite solar cells.
• The strategy significantly improves both small-area device efficiency and the stability of larger-area mini-modules.
• This work represents a significant advancement towards the scalable manufacturing of stable and efficient perovskite solar modules.