Dynamic Disulfide-Linked Dimeric Acceptors for High-Efficiency and Mechanically Robust Organic Solar Cells

Area of Science:

• Materials Science
• Organic Electronics
• Polymer Chemistry

Background:

• Organic solar cells (OSCs) are crucial for wearable electronics but require enhanced efficiency, stability, and mechanical properties.
• Existing OSC materials often compromise performance for flexibility or vice versa.

Purpose of the Study:

• To design and synthesize a novel photoactive material for OSCs with integrated dynamic covalent linkages.
• To improve the efficiency, thermal stability, and mechanical robustness of organic solar cells.

Main Methods:

• Synthesis of a disulfide-linked dimeric acceptor (DY-SS) with exchangeable dynamic covalent bonds.
• Fabrication and characterization of ternary organic solar cell devices incorporating DY-SS.
• Mechanical testing including bending cycles and toughness evaluation.

Main Results:

• Achieved a power conversion efficiency (PCE) of 20.40% in ternary devices.
• Extended the T80 thermal lifetime by 1.62-fold.
• Significantly enhanced film toughness (7.54-fold) and crack-onset strain (16.07%), with 91.1% efficiency retained after 10^5 bending cycles.

Conclusions:

• The dynamic covalent network in DY-SS enables adaptive material properties for improved mechanical durability.
• This molecular design strategy yields efficient, stable, and mechanically robust OSCs suitable for demanding applications.
• The study presents a new framework for developing high-performance organic electronic materials.