Interface Chelation Induced by Pyridine-Based Polymer for Efficient and Durable Air-Processed Perovskite Solar Cells

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Polymer doping is crucial for controlling perovskite crystal growth and improving electronic quality in perovskite solar cells (PSCs).
• Current methods often require controlled atmospheres, limiting large-scale production.

Purpose of the Study:

• To develop a novel self-healing polymer for doping perovskite films prepared in air.
• To enhance perovskite crystallinity, passivate grain boundaries, and improve the durability of PSCs.

Main Methods:

• A new self-healing polysiloxane (SHP) incorporating dynamic 2,6-pyridinedicarboxamide (PDCA) coordination units and hydrogen bonds was synthesized.
• SHP was incorporated into perovskite films, utilizing PDCA's coordination interactions (Pb²⁺-N_amido, I^--N_pyridyl, Pb²⁺-O_amido) and hydrogen bonds for film modification.
• The self-healing property of SHP was leveraged to repair cracks in grain boundaries of fatigued PSCs.

Main Results:

• The doped perovskite films exhibited enhanced crystallinity and passivated grain boundaries.
• The self-healing polysiloxane effectively repaired micro-cracks, improving device fatigue resistance.
• The resulting perovskite solar cell achieved a champion power conversion efficiency of 19.50% with significantly reduced hysteresis.

Conclusions:

• Heterocyclic-based macromolecular doping using self-healing polysiloxanes is a viable strategy for air-processed perovskite solar cells.
• This approach enhances both the efficiency and durability of PSCs, offering a promising route for commercialization.
• The study demonstrates the potential of dynamic coordination and hydrogen bonding in polymer design for advanced semiconductor applications.