Reinforcement of Cathode Interface Using a Dipolar Small Molecule for Enhancing Operational Stability of Perovskite...

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Inverted perovskite solar cells (PSCs) show promise for scalable, high-efficiency energy generation.
• Interfacial issues between the electron transport layer (ETL) and cathode hinder PSC performance and stability.
• Common challenges include energy level mismatch, ion migration, and cathode degradation.

Purpose of the Study:

• To introduce a novel quinoxaline-based high-dipole material (MQPPO) as a cathode interlayer (CIL) for p-i-n PSCs.
• To investigate MQPPO's potential to improve energy level alignment, charge extraction, and interfacial stability.
• To evaluate the impact of MQPPO on the power conversion efficiency (PCE) and long-term stability of PSCs.

Main Methods:

• Synthesis and characterization of the quinoxaline-based high-dipole material (MQPPO).
• Fabrication of PSC devices incorporating MQPPO as a CIL in p-i-n structures.
• Performance testing under 1 sun illumination to determine PCE and stability over 1440 hours.

Main Results:

• MQPPO incorporation significantly improved energy level alignment and charge extraction at the ETL-cathode interface.
• MQPPO-based PSCs achieved a high PCE of 21.65% under 1 sun illumination.
• Devices exhibited excellent long-term stability, retaining over 80% of their initial efficiency after 1440 hours of operation.

Conclusions:

• MQPPO serves as an effective CIL material for enhancing the performance and stability of inverted PSCs.
• The strong dipole moment and hydrophobic properties of MQPPO contribute to improved interfacial energetics and durability.
• MQPPO represents a promising advancement for developing high-performance, sustainable perovskite solar energy technologies.