Ternary Organic Solar Cells with Power Conversion Efficiency Approaching 15% by Fine-Selecting the Third Component

Area of Science:

• Materials Science
• Organic Electronics
• Photovoltaics

Background:

• Nonfullerene acceptors (NFAs) with moderate bandgaps are key components in ternary organic solar cells (OSCs).
• Ternary systems offer enhanced performance by incorporating a third component into a binary blend.

Purpose of the Study:

• To investigate the impact of chlorine (Cl) atom substitution on the end groups of F-series NFAs.
• To evaluate the influence of these modified NFAs as third components in PM6:BDT-Br based ternary OSCs.

Main Methods:

• Synthesis and characterization of F-H, F-Cl, and F-2Cl acceptors.
• Fabrication and performance testing of binary and ternary OSCs.
• Morphological analysis of blend films.

Main Results:

• F-Cl and F-2Cl acceptors improved blend film morphology, leading to ordered packing and high crystallinity.
• Ternary OSCs with F-Cl and F-2Cl achieved power conversion efficiencies (PCEs) of 13.89% and 14.67%, respectively.
• The F-H acceptor showed poor compatibility, resulting in a lower PCE of 10.79% for its ternary device.

Conclusions:

• F-series NFAs with moderate bandgaps are effective third components for high-performance ternary OSCs.
• Increased chlorine substitution on end groups, particularly in F-2Cl, enhances device performance.
• These findings suggest broad applicability of F-series acceptors in other binary systems for OSCs.