Trap suppression in ordered organic photovoltaic heterojunctions

Area of Science:

• Materials Science
• Organic Electronics
• Photovoltaics

Background:

• Organic solar cells (OSCs) suffer from high trap densities (10^16-10^18 cm^-3) due to weak intermolecular interactions and poor crystallinity of organic semiconductors.
• This leads to localized charge carriers, reduced carrier lifetime, low mobility, and significant non-radiative recombination, limiting power conversion efficiencies (PCEs).

Purpose of the Study:

• To review recent advancements in trap suppression strategies for OSCs.
• To explore how material design and device engineering can mitigate trap-related issues.
• To identify future research directions for enhancing OSC performance through trap suppression.

Main Methods:

• Review of literature on material design for improved crystallinity and molecular order in OSCs.
• Analysis of device engineering approaches aimed at reducing trap states.
• Synthesis of recent findings on trap suppression techniques.

Main Results:

• Improved crystallinity and molecular ordering of donor/acceptor materials effectively suppress traps in OSCs.
• Device engineering strategies offer further avenues for reducing trap density and enhancing charge transport.
• Targeted trap suppression is a critical factor for boosting OSC PCEs.

Conclusions:

• Material design and device engineering are crucial for overcoming trap-related limitations in OSCs.
• Further research into advanced trap suppression techniques will drive significant improvements in OSC performance.
• Optimizing molecular interactions and order is essential for high-efficiency organic solar cells.