Co-Assembled Hybrid Interlayer Engineering for Enhanced Upper Interface Stability in Inverted Perovskite Solar Cells

Area of Science:

• Materials Science
• Renewable Energy
• Nanotechnology

Background:

• Electron transport layer (ETL) interface engineering is crucial for high-efficiency and stable inverted perovskite solar cells (PSCs).
• Co-assembled hybrid interlayers for the ETL interface in PSCs are underexplored.
• Achieving high efficiency and operational stability simultaneously remains a challenge for PSCs.

Purpose of the Study:

• To develop a novel co-assembled hybrid interlayer for the ETL interface in inverted PSCs.
• To enhance the surface coverage and interfacial dipole moment at the ETL interface.
• To improve both the power conversion efficiency and long-term stability of PSCs.

Main Methods:

• Integration of 4-aminobenzoate acid hydrochloride (4AA) and dibenzo-18-crown-6 (DB18C6) to form a hybrid interlayer.
• Characterization of the interlayer's impact on surface coverage and interfacial dipole moment.
• Fabrication and testing of inverted PSCs with the modified ETL interface.

Main Results:

• The hybrid interlayer significantly increased surface coverage (0.57 to 0.79) and interfacial dipole moment (2 to 7 Debye).
• Modified PSCs achieved a power conversion efficiency of 26.33%, with improved open-circuit voltage (1.167 V) and fill factor (86.05%).
• Unencapsulated devices retained 93.2% of initial efficiency after 1000 hours of operation, demonstrating excellent stability.

Conclusions:

• The co-assembled hybrid interlayer effectively passivates defects and optimizes the ETL interface in inverted PSCs.
• This strategy significantly enhances both the efficiency and operational stability of PSCs.
• The developed interlayer provides a promising pathway for high-performance and durable perovskite solar cells.