Green-Solvent-Processable Low-Cost Fluorinated Hole Contacts with Optimized Buried Interface for Highly Efficient...

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Hole contact materials are crucial for perovskite solar cell (PSC) performance.
• Current materials often lack high performance, cost-effectiveness, or green-solvent processability, hindering PSC commercialization.

Purpose of the Study:

• To develop novel, low-cost, and green-solvent processable hole contact molecules for efficient PSCs.
• To investigate the impact of a fluorination strategy on molecular properties and device performance.

Main Methods:

• Synthesized two novel donor-acceptor (D-A) type hole contact molecules (FMPA-BT-CA and 2FMPA-BT-CA) using a fluorination strategy.
• Utilized alcohol-based solvents for solution processing.
• Fabricated inverted PSC devices incorporating the novel hole contact materials.

Main Results:

• Fluorination successfully lowered the highest occupied molecular orbital (HOMO) energy levels and increased dipole moments of the molecules.
• Improved interfacial interactions between the hole contacts and the perovskite layer were observed.
• Achieved a remarkable power conversion efficiency (PCE) of 22.37% with good light stability in green-solvent processed devices.

Conclusions:

• The developed fluorinated D-A molecules are promising candidates for high-performance, cost-effective, and environmentally friendly hole contacts in PSCs.
• Fluorination is an effective strategy to enhance molecular properties and device performance in PSCs.
• These findings contribute to the advancement of sustainable and efficient perovskite solar cell technology.