Multi-Functional Regulation on Buried Interface for Achieving Efficient Triple-Cation Perovskite Solar Cells

Area of Science:

• Materials Science
• Renewable Energy
• Semiconductor Physics

Background:

• Mixed-cation perovskite solar cells (PSCs) offer promising bandgaps and stability.
• Optimizing the perovskite/tin oxide (SnO2) interface is crucial for high-performance PSCs.
• Interface defects and energy level mismatch hinder device efficiency and longevity.

Purpose of the Study:

• To develop a multi-functional interface modification strategy for SnO2 in PSCs.
• To enhance the efficiency and operational stability of CsFAMA triple cation PSCs.
• To address challenges in perovskite/SnO2 interface design.

Main Methods:

• Introducing N-Chlorosuccinimide (NCS) into the SnO2 precursor solution.
• Utilizing NCS's C=O group for defect passivation at the buried interface.
• Leveraging NCS for in-situ pH adjustment and stress release in the perovskite layer.

Main Results:

• Achieved a champion power conversion efficiency (PCE) of 24.74% for ITO/SnO2/Perovskite/Spiro-OMeTAD/Ag devices.
• Demonstrated remarkable device stability, retaining 94.6% of initial PCE after 40 days at room temperature and 20% RH.
• Successfully passivated uncoordinated defects and optimized energy level alignment at the perovskite/SnO2 interface.

Conclusions:

• The proposed NCS-based interface engineering is a versatile approach for efficient and stable PSCs.
• This strategy effectively tackles multiple interface-related issues simultaneously.
• The findings pave the way for developing more robust and high-performing perovskite solar cell technologies.