2,2'-Bipyridyl-4,4'-Dicarboxylic Acid Modified Buried Interface of High-Performance Perovskite Solar Cells

Area of Science:

• Materials Science
• Renewable Energy
• Nanotechnology

Background:

• Interface engineering is crucial for high-performance perovskite solar cells (PSCs).
• Defects at the SnO2/perovskite interface limit device efficiency and stability.
• Developing effective interfacial layers is key to advancing PSC technology.

Purpose of the Study:

• To introduce 2,2 -bipyridyl-4,4 -dicarboxylic acid (HBPDC) as a novel interfacial layer in PSCs.
• To investigate the dual passivation mechanism of HBPDC on SnO2 and perovskite layers.
• To enhance the energy band alignment and charge transfer properties at the interface.

Main Methods:

• Incorporation of HBPDC as an interfacial layer between SnO2 and perovskite.
• Characterization of interfacial properties using techniques such as XPS and UPS.
• Fabrication and performance testing of PSC devices under standard conditions.

Main Results:

• HBPDC effectively passivates surface defects on both SnO2 and perovskite layers via esterification and Lewis acid-base interactions.
• Improved interfacial energy band alignment and facilitated electron transfer from perovskite to SnO2.
• Achieved a power conversion efficiency (PCE) of 25.41% and enhanced environmental stability.

Conclusions:

• HBPDC serves as a highly effective interfacial modifier for PSCs.
• The dual passivation and improved charge transfer contribute to enhanced device performance and stability.
• This work offers a promising strategy for developing next-generation, efficient, and stable perovskite solar cells.