Anthracene-based donor-acceptor low band gap polymers for application in solar cells.

Area of Science:

• Materials Science
• Organic Electronics
• Polymer Chemistry

Background:

• Conjugated polymers are crucial for organic electronics, particularly in developing efficient and cost-effective solar cells.
• Low band gap polymers are essential for maximizing light absorption in photovoltaic devices.
• Anthracene and benzo[c][1,2,5]thiadiazole units are known building blocks for high-performance conjugated polymers.

Purpose of the Study:

• To synthesize novel anthracene-based low band gap conjugated polymers.
• To investigate the photophysical, electrochemical, and photovoltaic properties of these new polymers.
• To evaluate their performance in bulk heterojunction solar cells.

Main Methods:

• Polymer synthesis via alternating copolymerization of 2,6-linked anthracene with dithienyl-benzo[c][1,2,5]thiadiazole or dibithiophenyl-benzo[c][1,2,5]thiadiazole units.
• Characterization of photophysical properties (absorption, emission).
• Electrochemical analysis (cyclic voltammetry) to determine energy levels.
• Fabrication and testing of bulk heterojunction solar cells using PC71BM as an electron acceptor.

Main Results:

• Successful preparation of anthracene-based low band gap conjugated polymers.
• Demonstrated tunable photophysical and electrochemical properties based on the specific thiophene-containing benzo[c][1,2,5]thiadiazole unit.
• Achieved promising photovoltaic performance in bulk heterojunction solar cells.

Conclusions:

• The synthesized anthracene-based conjugated polymers are viable candidates for organic photovoltaic applications.
• The incorporation of specific dithienyl- or dibithiophenyl-benzo[c][1,2,5]thiadiazole units allows for tuning of polymer properties.
• Further optimization holds potential for enhancing solar cell efficiency.