Conjugated Polymer Semiconductors Enabled Multifunctional Interfacial Engineering for High-Performance Inverted...

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Interfacial defects between perovskite and electron transport layers (ETLs) hinder industrialization of perovskite solar cells.
• Achieving high efficiency and long-term stability simultaneously remains a critical challenge.

Purpose of the Study:

• To develop a novel interface interlayer to address the perovskite/ETL defect challenge.
• To improve the efficiency and operational stability of inverted perovskite solar cells.

Main Methods:

• Developed a multifunctional integrated polymer semiconductor, P4N-Cl, as an interface interlayer.
• Utilized synergistic coordination mechanism of functional groups (carbonyl, Cl, sp2-N) for defect passivation.
• Optimized energy level alignment and charge carrier dynamics at the perovskite/ETL interface.

Main Results:

• P4N-Cl effectively passivated interfacial defects and suppressed non-radiative recombination.
• Achieved a champion power conversion efficiency of 26.20% with an open-circuit voltage of 1.21 V.
• Demonstrated excellent stability: 96.2% efficiency after 2016h aging in ambient air and 90.2% after 1500h under operational stress.

Conclusions:

• The P4N-Cl interlayer offers a "one-stop" solution for high-efficiency, stable perovskite solar cells.
• This design presents promising prospects for next-generation commercial perovskite solar cells.
• Effective defect passivation and enhanced charge dynamics are key to device performance and longevity.