Finely Tuned Molecular Packing Realized by a New Rhodanine-Based Acceptor Enabling Excellent Additive-Free Small- and...

Area of Science:

• Materials Science
• Organic Electronics
• Photovoltaics

Background:

• Organic solar cells (OSCs) offer a promising alternative for renewable energy generation.
• Ternary blend systems are explored to enhance OSC performance by optimizing morphology.
• Nonfullerene acceptors (NFAs) are crucial components in state-of-the-art OSCs.

Purpose of the Study:

• To synthesize and characterize a new NFA, BTA-ERh.
• To investigate the effect of BTA-ERh on blend film morphology in a PM6:Y7:PC71BM system.
• To evaluate the photovoltaic performance and stability of additive-free quaternary OSCs.

Main Methods:

• Synthesis of the nonfullerene acceptor BTA-ERh.
• Fabrication of ternary and quaternary organic solar cells using PM6, Y7, PC71BM, and BTA-ERh.
• Characterization of blend film morphology, including phase separation and crystallinity.
• Performance testing of small-area devices and large-area modules.

Main Results:

• BTA-ERh integration optimized blend film morphology, improving exciton dissociation and charge transport.
• Additive-free quaternary devices achieved a power conversion efficiency (PCE) of 18.90%.
• Large-area modules (55 cm²) demonstrated a PCE of 12.20% via D-bar coating in air.
• The devices exhibited good operational stability.

Conclusions:

• The developed NFA, BTA-ERh, effectively tunes morphology for high-performance OSCs.
• Multicomponent strategies are viable for creating additive-free, high-efficiency OSCs.
• This approach holds significant potential for scalable and stable organic solar cell applications.