Optimizing Photovoltaic Performance through Functional End-Capping Units of Polymer Donor Materials

Area of Science:

• Materials Science
• Organic Electronics
• Photovoltaics

Background:

• Organic solar cells (OSCs) require high-performance active layers, typically polymer donors and small molecule acceptors.
• Enhanced polymer donor properties like crystallinity and molecular packing improve charge transport and device performance.

Purpose of the Study:

• To synthesize and evaluate a novel polymer donor, D18-6F, for improved organic solar cell performance.
• To investigate the impact of end-capping with a trifluorophenylthiophene unit on polymer properties and device efficiency.

Main Methods:

• Synthesis of the D18-6F polymer donor.
• Characterization of molecular packing, crystallinity, and miscibility.
• Fabrication and testing of organic solar cell devices.

Main Results:

• D18-6F demonstrated enhanced intermolecular interactions, ordered molecular packing, and crystallinity compared to the parent polymer.
• Improved miscibility and optimized blend film morphology were observed.
• Organic solar cells utilizing D18-6F achieved a power conversion efficiency of 19.45%, an increase from 18.47%.

Conclusions:

• The end-capping strategy using 2-(3,4,5-trifluorophenyl)thiophene effectively improved polymer donor properties.
• D18-6F represents a promising material for high-efficiency organic solar cells.
• This approach offers a valuable pathway for designing advanced polymer donors for photovoltaic applications.