Anchoring Vertical Dipole to Enable Efficient Charge Extraction for High-Performance Perovskite Solar Cells

Area of Science:

• Materials Science
• Renewable Energy

Background:

• Perovskite solar cells (PSCs) fabricated using the two-step sequential method offer high reproducibility and low costs.
• Challenges include high trap-state density and inefficient charge carrier extraction.

Purpose of the Study:

• To develop highly efficient and stable PSCs using organic-inorganic (OI) complexes as multifunctional interlayers.
• To address trap states and improve charge carrier extraction in PSCs.

Main Methods:

• Fabrication of PSCs via a two-step sequential method.
• Incorporation of organic-inorganic (OI) complexes as multifunctional interlayers.
• Molecular design of OI complexes to create a vertical dipole moment.

Main Results:

• The OI complexes reduced trap states by interacting with under-coordinated Pb2+ ions.
• The interlayer's dipole moment enhanced the built-in electric field, improving charge carrier extraction.
• A champion power conversion efficiency of 23.55% was achieved with negligible hysteresis.
• The devices demonstrated excellent ambient stability, retaining 91% of initial efficiency after 3000 hours of storage due to the hydrophobicity of the OI complexes.

Conclusions:

• Organic-inorganic complexes are effective multifunctional interlayers for enhancing PSC performance.
• Rational molecular design of interlayers can significantly boost efficiency and stability.
• The developed PSCs show great promise for commercial applications due to their high efficiency and durability.