Dithienoindophenines: p-Type Semiconductors Designed by Quinoid Stabilization for Solar-Cell Applications

Area of Science:

• Organic electronics
• Materials science
• Photovoltaics

Background:

• Quinoidal conjugated materials offer potential for photovoltaics due to their unique electronic properties.
• Their rigid and planar structures are underexplored compared to aromatic counterparts.
• Existing research lacks focus on quinoidal materials' photovoltaic applications.

Purpose of the Study:

• To design and synthesize novel dithienoindophenine derivatives (DTIPs).
• To stabilize the quinoidal resonance within the indophenine framework.
• To investigate the photovoltaic performance and charge transport properties of DTIPs.

Main Methods:

• Synthesis of dithienoindophenine derivatives (DTIPs).
• Characterization of molecular configuration and electronic properties.
• Fabrication and testing of organic photovoltaic devices.

Main Results:

• DTIPs were successfully synthesized, exhibiting a fixed molecular configuration.
• DTIPs function as p-type semiconductors with high unipolar hole mobilities (up to 0.22 cm²/V·s).
• Optimal power conversion efficiency (PCE) of 4.07% was achieved, outperforming aromatic bithieno[3,4-b]thiophene (BTT) counterparts.

Conclusions:

• Stabilized quinoidal DTIPs demonstrate superior charge transport properties compared to parent indophenine derivatives.
• DTIPs represent a promising class of materials for efficient organic photovoltaic applications.
• The findings encourage further exploration of quinoidal structures in organic electronics.