Benzo/Naphthodifuranone-Based Polymers: Effect of Perpendicular-Extended Main Chain π-Conjugation on Organic Field-Effect Transistor Performances.

Affiliation

Li R(1), Dai Z(1), Zheng M(1)(2), Wang C(1), Deng Z(3), Zhuang T(1), Feng K(4), Yang W(1), Yang K(4), Zhang H(1).
Author information:
(1)Key Laboratory of Rubber-Plastics of Ministry of Education/Shandong Province
(QUST), School of Polymer Science and Engineering, Qingdao University of Science and Technology, 53-Zhengzhou Road, Qingdao, 266042, P. R. China.
(2)Qingdao Haiwan Science and Technology Industry Research Institute Co., Ltd., No. 27 Banghai South Road Shibei District, Qingdao, 266031, P. R. China.
(3)Department of Materials Science and Engineering, Southern University of Science and Technology
(SUSTech), No. 1088, Xueyuan Road, Shenzhen, Guangdong, 518055, P. R. China.
(4)National and Local Joint Engineering Laboratory for Slag Comprehensive Utilization and Environmental Technology, School of Material Science and Engineering, Shaanxi University of Technology
(SNUT), Hanzhong, 723001, P. R. China.

Abstract

For polymer semiconductors, the backbone structure plays an essential role in determining their physicochemical properties and charge transport behaviors. In this work, two donor-acceptor-type polymers (P-BDF and P-NDF) based on benzodifuranone (BDF) and naphthodifunarone (NDF) as electron-deficient moieties and indaceno-dithiophene as electron-rich groups are designed, synthesized and, for the first time, applied in organic field-effect transistor. P-BDF and P-NDF differ from their backbone structures while P-BDF has a more planar backbone conformation due to its smaller conjugated core size and P-NDF features a perpendicular-extended main chain structure. As a result, P-BDF polymer exhibits bathochromic optical absorption, deeper molecular orbital energy levels, and more importantly, closer π-stacking and stronger aggregation in the solid state and thus affords a more promising hole mobility of up to 0.85 cm2 V-1 s-1 in OFET devices, while that of the P-NDF-based devices is only 0.55 cm2 V-1 s-1 . The results suggest the great potential of BDF/NDF-type chromophores in constructing novel organic semiconductors and also indicate that the main chain coplanarity of polymer semiconductors is more essential than the sole extension of π-conjugations (especially at the perpendicular direction of polymer main chains) for the design of high-performance OFET materials.