TY - JOUR
T1 - Fluorine-Substituted Dithienylbenzodiimide-Based n-Type Polymer Semiconductors for Organic Thin-Film Transistors
AU - Feng, Kui
AU - Zhang, Xianhe
AU - Wu, Ziang
AU - Shi, Yongqiang
AU - Su, Mengyao
AU - Yang, Kun
AU - Wang, Yang
AU - Sun, Huiliang
AU - Min, Jie
AU - Zhang, Yujie
AU - Cheng, Xing
AU - Woo, Han Young
AU - Guo, Xugang
N1 - Funding Information:
X.G. thanks the National Science Foundation of China (51573076), the Shenzhen Basic Research Fund (JCYJ20170817105905899), and the Shenzhen Peacock Plan Project (KQTD20140630110339343). H.Y.W. is grateful for the financial support from the National Research Foundation of Korea (2016M1A2A2940911 and 2015M1A2A2057506).
Publisher Copyright:
© 2019 American Chemical Society.
PY - 2019/10/2
Y1 - 2019/10/2
N2 - Imide functionalization is one of the most effective approaches to develop electron-deficient building blocks for constructing n-type organic semiconductors. Driven by the attractive properties of imide-functionalized dithienylbenzodiimide (TBDI) and the promising device performance of TBDI-based polymers, a novel acceptor with increased electron affinity, fluorinated dithienylbenzodiimide (TFBDI), was designed with the hydrogen replaced by fluorine on the benzene core, and the synthetic challenges associated with this highly electron-deficient fluorinated imide building block are successfully overcome. TFBDI showed suppressed frontier molecular orbital energy levels as compared with TBDI. Copolymerizing this new electron-withdrawing TBDI with various donor co-units afforded a series of n-type polymer semiconductors TFBDI-T, TFBDI-Se, and TFBDI-BSe. All these TFBDI-based polymers exhibited a lower-lying lowest unoccupied molecular orbital (LUMO) energy level than the polymer analogue without fluorine. When applied in organic thin-film transistors, three polymers showed unipolar electron transport with large on-current/off-current ratios (Ion/Ioff) of 105-107. Among them, the selenophene-based polymer TFBDI-Se with the deepest-positioned LUMO and optimal chain stacking exhibited the highest electron mobility of 0.30 cm2 V-1 s-1. This result demonstrates that the new TFBDI is a highly attractive electron-deficient unit for enabling n-type polymer semiconductors, and the fluorination of imide-functionalized arenes offers an effective approach to develop more electron-deficient building blocks in organic electronics.
AB - Imide functionalization is one of the most effective approaches to develop electron-deficient building blocks for constructing n-type organic semiconductors. Driven by the attractive properties of imide-functionalized dithienylbenzodiimide (TBDI) and the promising device performance of TBDI-based polymers, a novel acceptor with increased electron affinity, fluorinated dithienylbenzodiimide (TFBDI), was designed with the hydrogen replaced by fluorine on the benzene core, and the synthetic challenges associated with this highly electron-deficient fluorinated imide building block are successfully overcome. TFBDI showed suppressed frontier molecular orbital energy levels as compared with TBDI. Copolymerizing this new electron-withdrawing TBDI with various donor co-units afforded a series of n-type polymer semiconductors TFBDI-T, TFBDI-Se, and TFBDI-BSe. All these TFBDI-based polymers exhibited a lower-lying lowest unoccupied molecular orbital (LUMO) energy level than the polymer analogue without fluorine. When applied in organic thin-film transistors, three polymers showed unipolar electron transport with large on-current/off-current ratios (Ion/Ioff) of 105-107. Among them, the selenophene-based polymer TFBDI-Se with the deepest-positioned LUMO and optimal chain stacking exhibited the highest electron mobility of 0.30 cm2 V-1 s-1. This result demonstrates that the new TFBDI is a highly attractive electron-deficient unit for enabling n-type polymer semiconductors, and the fluorination of imide-functionalized arenes offers an effective approach to develop more electron-deficient building blocks in organic electronics.
KW - dithienylbenzodiimide
KW - fluorination
KW - imide functionalization
KW - n-type polymer semiconductors
KW - organic thin-film transistors
UR - http://www.scopus.com/inward/record.url?scp=85072849338&partnerID=8YFLogxK
U2 - 10.1021/acsami.9b13138
DO - 10.1021/acsami.9b13138
M3 - Article
C2 - 31525945
AN - SCOPUS:85072849338
VL - 11
SP - 35924
EP - 35934
JO - ACS applied materials & interfaces
JF - ACS applied materials & interfaces
SN - 1944-8244
IS - 39
ER -