Fused-Ring Electron Acceptors for Photovoltaics and Beyond

Area of Science:

• Materials Science
• Organic Electronics
• Photovoltaics

Background:

• Organic solar cells (OSCs) and perovskite solar cells (PSCs) are promising renewable energy technologies.
• Fullerene derivatives dominated OSC acceptors until 2015 but have limitations in absorption and stability.
• Existing non-fullerene acceptors like rylene diimides show potential but require further development.

Purpose of the Study:

• To review the development and applications of fused-ring electron acceptors (FREAs).
• To highlight the advantages of FREAs over traditional fullerene acceptors in OSCs.
• To explore the potential of FREAs in PSCs and other advanced applications.

Main Methods:

• Development of modular molecular structures for tailored electronic and optical properties.
• Synthesis and purification strategies for scalable production of FREAs.
• Device engineering and characterization to evaluate performance in OSCs and PSCs.

Main Results:

• FREAs exhibit broad absorption (700-1000 nm), high electron mobility, and tunable energy levels.
• OSCs utilizing FREAs achieved power conversion efficiencies (PCEs) up to 18%, initiating the non-fullerene era.
• FREAs demonstrated improved efficiency and stability in PSCs and potential in photodetectors and transistors.

Conclusions:

• FREAs represent a significant advancement in electron acceptor materials for solar cells.
• The modular design of FREAs allows for continuous performance optimization and commercialization.
• FREAs offer versatile applications beyond photovoltaics, including photothermal therapy and solar water splitting.