1D Mixed-Stack Cocrystals Based on Perylene Diimide toward Ambipolar Charge Transport

Area of Science:

• Materials Science
• Organic Electronics
• Solid-State Chemistry

Background:

• Organic ambipolar semiconductors are crucial for advanced electronic devices but remain limited.
• Electron donor-acceptor alternative stacking offers a promising motif for developing new organic semiconductors.

Purpose of the Study:

• To synthesize and characterize novel 1D mixed-stack cocrystals for organic ambipolar semiconductor applications.
• To investigate the structure-property relationships influencing charge transport in these cocrystals.

Main Methods:

• Synthesis of four 1D mixed-stack cocrystals using N,N'-bis(perfluorobutyl)-1,7-dicyanoperylene-3,4:9,10-bis(dicarboximide) (PDICNF) as acceptor and various donors.
• Characterization using single-crystal X-ray analysis, absorption spectra, fluorescence quenching, Job's curve plot, and polarized photoluminescence.
• Theoretical calculations to understand charge transfer and coassembly behaviors.

Main Results:

• Achieved four 1D mixed-stack cocrystals with D:A ratio of 1:1 via solution or vapor processing.
• Pyrene-PDICNF cocrystals exhibited the highest electron mobility (0.19 cm² V⁻¹ s⁻¹) among perylene diimide-based cocrystals.
• DPTTA-PDICNF cocrystals demonstrated well-balanced electron and hole mobility (1.7 × 10⁻² and 2.0 × 10⁻² cm² V⁻¹ s⁻¹, respectively) due to strong superexchange interactions.

Conclusions:

• Established a viable strategy for designing 1D mixed-stack cocrystals with excellent ambipolar transport properties.
• The donor-acceptor alternative stacking along the long axis is key to achieving high charge mobility.
• These findings pave the way for developing high-performance organic ambipolar semiconductors.