Perylene Monoimide Phosphorus Salt Interfacial Modified Crystallization for Highly Efficient and Stable Perovskite...

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Interfacial defects in perovskite films limit perovskite solar cell (PSC) performance.
• Effective interface modification is crucial for enhancing PSC efficiency and stability.

Purpose of the Study:

• To design and utilize novel perylene monoimide (PMI) derivative phosphonium bromide salts for interface modification in PSCs.
• To investigate the bidirectional passivation effect of PMI derivatives on the SnO2/perovskite interface.
• To enhance the performance and stability of PSCs and explore their potential in flexible devices.

Main Methods:

• Synthesized two PMI derivative phosphonium bromide salts.
• Incorporated PMI derivatives as an interface layer between SnO2 and perovskite.
• Characterized the structural, electronic, and performance properties of the modified PSCs.
• Evaluated device stability under continuous illumination and assessed flexibility.

Main Results:

• PMI derivatives effectively passivated interfacial defects and reduced oxygen vacancies on the SnO2 surface.
• The electron transport layer energy level was tuned for better alignment with the perovskite layer.
• Perovskite crystal growth was promoted, leading to reduced film defects.
• Power conversion efficiency (PCE) increased from 19.49% to 22.85%, and open-circuit voltage (VOC) rose from 1.06 V to 1.14 V.
• Devices maintained 88% of initial PCE after 240 hours of continuous illumination.
• The quasi-planar structure of PMI derivatives improved the flexibility of PSCs.

Conclusions:

• PMI derivatives offer a promising strategy for interfacial engineering in PSCs.
• This approach significantly enhances PSC efficiency, stability, and flexibility.
• The study provides valuable insights for developing next-generation perovskite solar technologies.