Abstract
Diketopyrrolopyrrole (DPP)-based copolymers have received considerable attention as promising semiconducting materials for high-performance organic thin-film transistors (OTFTs). However, these polymers typically exhibit p-type or ambipolar charge-transporting characteristics in OTFTs due to their high-lying highest occupied molecular orbital (HOMO) energy levels. In this work, a new series of DPP-based n-type polymers have been developed by incorporating fused bithiophene imide oligomers (BTIn) into DPP polymers. The resulting copolymers BTIn-DPP show narrow band gaps as low as 1.27 eV and gradually down-shifted frontier molecular orbital energy levels upon the increment of imide group number. Benefiting from the coplanar backbone conformation, well-delocalized π-system, and favorable polymer chain packing, the optimal polymer in the series shows promising n-type charge transport with an electron mobility up to 0.48 cm2 V−1 s−1 in OTFTs, which is among the highest values for the DPP-based n-type polymers reported to date. The results demonstrate that incorporating fused bithiophene imide oligomers into polymers can serve as a promising strategy for constructing high-performance n-type polymeric semiconductors.
Original language | English |
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Article number | 1900394 |
Journal | Macromolecular Rapid Communications |
Volume | 40 |
Issue number | 23 |
DOIs | |
Publication status | Published - 2019 Dec 1 |
Bibliographical note
Publisher Copyright:© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Keywords
- bithiophene imide
- diketopyrrolopyrrole
- n-type polymer semiconductors
- organic thin-film transistors
ASJC Scopus subject areas
- Organic Chemistry
- Polymers and Plastics
- Materials Chemistry