Multiple-Noncovalent-Interaction-Stabilized Layered Dion-Jacobson Perovskite for Efficient Solar Cells

Area of Science:

• Materials Science
• Renewable Energy
• Solid-State Chemistry

Background:

• Two-dimensional (2D) Dion-Jacobson (DJ) perovskites offer enhanced structural stability compared to Ruddlesden-Popper (RP) perovskites.
• The underlying mechanisms for this improved stability in DJ perovskites remain largely uninvestigated.
• Developing novel spacer materials is crucial for advancing 2D perovskite solar cell performance.

Purpose of the Study:

• To develop a novel multifluorinated aromatic spacer for 2D DJ perovskites.
• To elucidate the role of noncovalent interactions in enhancing the stability of DJ perovskites.
• To optimize 2D DJ perovskite solar cells (PSCs) for high efficiency and stability.

Main Methods:

• Synthesis and characterization of a new multifluorinated aromatic spacer (4F-PhDMA).
• Fabrication and testing of 2D DJ perovskite solar cells incorporating the 4F-PhDMA spacer.
• Investigation of noncovalent interactions and dissociation energy using computational or experimental methods.

Main Results:

• The 4F-PhDMA spacer significantly increased the dissociation energy of the 2D DJ perovskite due to multiple noncovalent interactions.
• The optimized 2D DJ PSC with the 4F-PhDMA spacer achieved a champion power conversion efficiency (PCE) of 16.62%.
• The device demonstrated substantially improved light and thermal stability compared to control devices with unfluorinated spacers.

Conclusions:

• Multifluorinated aromatic spacers effectively enhance the stability of 2D DJ perovskites through strong noncovalent interactions.
• The developed 4F-PhDMA spacer is a promising component for high-performance and stable DJ perovskite solar cells.
• This work underscores the importance of rational spacer design in advancing 2D perovskite solar technology.