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From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Crystal engineering of dual channel p/n organic semiconductors by complementary hydrogen bonding
Hayden T Black1, Dmitrii F Perepichka
1Department of Chemistry and Centre for Self-Assembled Chemical Structures, McGill University, Montreal, Qc H3A OB8 (Canada).
Abstract:
The supramolecular arrangement of organic semiconductors in the solid state is as critical for their device properties as the molecular structure, but is much more difficult to control. To enable supramolecular design of semiconducting materials, we introduced dipyrrolopyridine as a new donor semiconductor capable of complementary hydogen bonding with naphthalenediimide acceptors. Through a combination of solution, crystallographic, and device studies, we show that the self-assembly driven by H bonding a) modulates the charge-transfer interactions between the donor and acceptor, b) allows for precise control over the solid-state packing, and c) leads to a combination of the charge-transport properties of the individual components. The predictive power of this approach was demonstrated in the synthesis of three new coassembled materials which show both hole and electron transport in single-crystal field-effect transistors. These studies provide a foundation for advanced solid-state engineering in organic electronics, capitalizing on the complementary H bonding.
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