Buried Interface Regulation with a Supramolecular Assembled Template Enables High-Performance Perovskite Solar Cells...

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Perovskite solar cells (PSCs) show great promise but suffer from open-circuit voltage (V_OC) deficits below the Shockley-Queisser limit.
• Energy-level mismatch and non-radiative recombination at interfaces are primary limitations for V_OC.
• Existing passivation methods often provide only incidental contact, limiting effectiveness.

Purpose of the Study:

• To develop a strategy to overcome V_OC limitations in PSCs.
• To improve perovskite crystallization and interface properties.
• To enhance both the efficiency and operational stability of PSCs.

Main Methods:

• Constructed a perovskite crystallization-driven template at the SnO₂/perovskite interface using a self-assembled amphiphilic phosphonate derivative.
• Utilized a solid-solid phase transition for evolutionary selection growth of the supramolecular template.
• Investigated the effect of the template on perovskite crystal orientation, carrier dynamics, and interface defect passivation.

Main Results:

• Achieved a highly preferred (100) orientation of perovskite crystals, facilitating carrier extraction.
• Demonstrated effective passivation of surface defects at the buried interface.
• Resulting PSCs achieved a power conversion efficiency (PCE) of 25.34% with a V_OC of 1.23 V, reaching 97.2% of the theoretical limit.
• Enhanced long-term operational stability under thermal and moisture stress, with T₉₂ lifetime exceeding 1200 hours.

Conclusions:

• The developed self-assembly strategy effectively addresses V_OC limitations by controlling perovskite crystallization and interface quality.
• This approach significantly boosts PSC performance and stability, offering a pathway towards highly efficient and durable perovskite photovoltaics.
• The method provides a marked improvement over conventional passivation techniques.