Chlorine-mediated strategy for organic photovoltaics

Area of Science:

• Photovoltaics
• Materials Science
• Organic Electronics

Background:

• Organic solar cells (OSCs) are a promising renewable energy technology with rapidly improving power conversion efficiencies (PCEs).
• Enhancing the performance and stability of OSCs is critical for their commercial viability.
• Novel materials and device architectures are essential for continued progress in OSC technology.

Purpose of the Study:

• To review chlorine-mediated photovoltaic materials developed by the research group.
• To demonstrate how controlling energy levels and molecular stacking impacts OSC performance.
• To present high-performance non-fullerene acceptors (NFAs) and quasi-planar heterojunction (Q-PHJ) devices.

Main Methods:

• Synthesis and characterization of chlorine-mediated organic photovoltaic materials.
• Control of material energy levels, molecular stacking, and aggregation behavior.
• Single-crystal analysis to understand chlorine-mediated interactions and their effect on molecular packing.
• Fabrication and testing of quasi-planar heterojunction (Q-PHJ) devices.

Main Results:

• Chlorine-mediated interactions significantly influenced molecular stacking and energy levels.
• Development of high-performance non-fullerene acceptors (NFAs) with 3D network stacking.
• Achieved improved performance in OSCs through tailored material design.
• Demonstrated enhanced stability in quasi-planar heterojunction (Q-PHJ) devices.

Conclusions:

• Chlorine-mediated materials provide a valuable strategy for designing efficient organic solar cells.
• Quasi-planar heterojunction (Q-PHJ) devices exhibit significant stability advantages.
• The findings offer guidance for developing next-generation efficient and stable organic solar cells.