Aza-substitution on naphthalene diimide-based conjugated polymers for n-type bottom gate/top contact polymer transistors under ambient conditions. Issue 2 (16th December 2020)

• Record Type: Journal Article
• Authors: Zhang, Guobing; Yu, Hao; Sun, Yue; Wang, Weiwei; Zhao, Yao; Wang, Lichun; Qiu, Longzhen; Ding, Yunsheng
• Is Part Of: Journal of materials chemistry. Volume 9:Issue 2(2021)
• Page Start: 633
• Page End: 639
• Publication Date: 2020-12-16
• Subjects: Materials -- Periodicals; Chemistry, Analytic -- Periodicals; Optical materials -- Research -- Periodicals; Electronics -- Materials -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d0tc04493h
• Languages: English
• ISSNs: 2050-7526

Abstract

Abstract : Four conjugated polymers based on naphthalene diimide (NDI) as the acceptor and thiophene–phenyl–thiophene with different aza-substitutions as co-units were synthesized. Abstract : Four conjugated polymers based on naphthalene diimide (NDI) as the acceptor and thiophene–phenyl–thiophene with different aza-substitutions as co-units were synthesized. The aza-substitution gradually lowered the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energy levels. The polymer with four aza-substitutions exhibited the deepest LUMO/HOMO energy level (−4.10/−6.01 eV). Consequently, organic field-effect transistors (OFETs) based on the bottom-gate/top-contact configuration exhibited unipolar electron transport characteristics even if the devices were exposed directly to ambient conditions. Furthermore, the corresponding devices also maintained their n-type transport behavior during long-term storage in air (>300 days). This work demonstrated that the incorporation of nitrogen atoms into NDI-based conjugated polymers for further lowering the energy levels is a feasible strategy for the construction of air-stable n-type unencapsulated OFETs.