Conjugated Polymers Based on Thiazole Flanked Naphthalene Diimide for Unipolar n-Type Organic Field-Effect Transistors

• DOI: 10.1021/acs.chemmater.8b03902
• Publication Date: 2018-11-08T23:35:49Z
• Authors: Long Zhang; Zhongli Wang; Chunhui Duan; Zhenfeng Wang; Yunfeng Deng; Jiantie Xu; Fei Huang; Yong Cao
• Keywords: 02 engineering and technology; 0210 nano-technology

This paper reports the rational design and synthesis of a novel electron-withdrawing building block, thiazole flanked naphthalene diimide (TzNDI), which offers a coplanar conformation and deep-lying highest-occupied molecular orbitals energy level in resulting conjugated polymers. A series of conjugated polymers (PTzNDI-2FT, PTzNDI-T, PTzNDI-Se, and PTzNDI-2T) consisting of TzNDI and different donor units were synthesized and characterized. The polymers all possess a high molecular weight and excellent thermal property. Their intense light absorption in low energy bands suggests an enhanced intramolecular charge transfer. The organic field-effect transistors (OFETs) based on these polymers exhibit unipolar n-type transport characteristics with low off current and high on–off current ratio. More importantly, all the devices exhibit near ideal transfer curves with kink-free transfer characteristics. Among these polymers, PTzNDI-2FT exhibits the highest electron mobility (μe) of 0.57 cm2 V–1 s–1, outperformi...