Copolymers of Bis-Diketopyrrolopyrrole and Benzothiadiazole Derivatives for High-Performance Ambipolar Field-Effect Transistors on Flexible Substrates

Jinyang Chen; Yingying Jiang; Jie Yang; Yunlong Sun; Longxian Shi; Yang Ran; Qingsong Zhang; Yuanping Yi; Shuai Wang; Yunlong Guo; Yunqi Liu

doi:10.1021/acsami.7b16516

Copolymers of Bis-Diketopyrrolopyrrole and Benzothiadiazole Derivatives for High-Performance Ambipolar Field-Effect Transistors on Flexible Substrates

ACS Appl Mater Interfaces. 2018 Aug 8;10(31):25858-25865. doi: 10.1021/acsami.7b16516. Epub 2018 Jan 26.

Authors

Jinyang Chen^{1

2}, Yingying Jiang^{1

2}, Jie Yang^{1

3}, Yunlong Sun^{1

2}, Longxian Shi^{1

2}, Yang Ran^{1

2}, Qingsong Zhang^{1

2}, Yuanping Yi¹, Shuai Wang³, Yunlong Guo¹, Yunqi Liu¹

Affiliations

¹ Key Laboratory of Organic Solids, Beijing National Laboratory for Molecular Sciences , Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190 , China.
² University of Chinese Academy of Sciences , Beijing 100049 , China.
³ Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, School of Chemistry and Chemical Engineering , Huazhong University of Science and Technology , Wuhan 430074 , China.

PMID: 29373010
DOI: 10.1021/acsami.7b16516

Abstract

We develop an "acceptor dimerization" strategy by a bis-diketopyrrolopyrrole (2DPP) for an ambipolar organic semiconductor. Copolymers of 2DPP and benzothiadiazole (BTz) derivatives, P2DPP-BTz and P2DPP-2FBTz, are designed and synthesized. Both of the polymers exhibit narrow optical bandgaps of ca. 1.30 eV. The strong electron-withdrawing property of 2DPP results in low-lying lowest unoccupied molecular orbital (LUMO) energy levels of the polymers, improving the electron mobilities. 2D grazing incident X-ray diffraction and atomic force microscopy indicate that the P2DPP-BTz exhibits a small π-π stacking distance of 3.59 Å and a smooth interface, thus promoting high mobility. To take full advantage of the flexibility of organic semiconductors, flexible field-effect transistors (FETs) were fabricated on poly(ethylene terephthalate) (PET) substrates. The FETs based on P2DPP-BTz show high performance with hole and electron mobilities of 1.73 and 2.58 cm² V^-1 s^-1, respectively. Our results demonstrate that the 2DPP acceptor is a promising building block for high-mobility ambipolar polymers.

Keywords: ambipolar polymer; bis-diketopyrrolopyrrole; field-effect transistor; flexible substrate; “acceptor dimerization” strategy.