TY - JOUR
T1 - Dithienylbenzodiimide
T2 - A new electron-deficient unit for n-type polymer semiconductors
AU - Chen, Jianhua
AU - Zhang, Xianhe
AU - Wang, Gang
AU - Uddin, Mohammad Afsar
AU - Tang, Yumin
AU - Wang, Yulun
AU - Liao, Qiaogan
AU - Facchetti, Antonio
AU - Marks, Tobin J.
AU - Guo, Xugang
N1 - Funding Information:
X. G. thanks the National Science Foundation of China (51573076), the Shenzhen Peacock Plan Project (KQTD20140630110339343), the Shenzhen Basic Research Fund (JCYJ20160530185244662), the Shenzhen Key Lab funding (ZDSYS201505291525382), the Guangdong Natural Science Foundation (2015A030313900), and the South University of Science and Technology of China (FRG-SUSTC1501A-72). J. C. thanks the SUSTC Presidential Postdoctoral Fellowship. X. Z. is grateful to the Undergraduate Student Innovation Training Program (2016X14). T. J. M. acknowledges financial support from Argonne-Northwestern Solar Energy Research (ANSER) Center, an Energy Frontier Research Center funded by the US Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0001059. Use of the Advanced Photon Source, an Office of Science User Facility operated for the US Department of Energy (DOE) Office of Science by Argonne National Laboratory, was supported by the US DOE under Contract No. DE-AC02-06CH11357.
PY - 2017
Y1 - 2017
N2 - Inspired by the excellent device performance of imide-functionalized polymer semiconductors in organic electronics, a novel imide-based building block, dithienylbenzodiimide (TBDI), with fused backbone is designed and synthesized. Single-crystal structure analysis reveals that the TBDI unit features non-planar backbone conformation but with a tight π-stacking distance of 3.36 Å. By copolymerizing with various electron-rich co-units, a series of TBDI-based polymer semiconductors is synthesized and the optoelectronic, thermal, electrochemical and charge transport properties of the semiconductors are characterized. Attributed to the non-planar backbone and intrinsic electrical property of TBDI, all polymers exhibit wide bandgaps (∼2.0 eV) with low-lying HOMOs (<-5.5 eV). Organic thin-film transistors are fabricated by incorporating the TBDI-based polymers as the active layer to investigate their charge transport properties. The dithienylbenzodiimide-bithiophene copolymer shows ambipolar transport characteristics with an electron and hole mobility of 0.15 and 0.015 cm2 V-1 s-1, respectively. By incorporating weaker electron donor co-units, the dithienylbenzodiimide-thiophene and dithienylbenzodiimide-difluorobithiophene copolymers exhibit unipolar n-channel transistor performance with electron mobility up to 0.11 and 0.34 cm2 V-1 s-1, respectively. Most high-performance n-channel polymer semiconductors reported to date typically show narrow bandgaps with high-lying HOMOs, resulting in substantial p-channel performance. The new TBDI-based wide bandgap polymers with low-lying HOMOs greatly suppress p-channel performance and lead to improved Ion/Ioff ratios. The excellent n-channel performance is attributed to the strong electron-withdrawing capability of imide groups, low-lying frontier molecular orbitals, compact π-stacking distance, and a high degree of film crystallinity as confirmed by GIWAXS analysis with distinct interlamellar and π-stacking diffraction patterns. The result reveals that a building block with non-planar backbone can be utilized for constructing high crystalline polymer semiconductors with substantial charge carrier mobility. The study indicates that dithienylbenzodiimide is a promising unit for synthesizing wide bandgap polymeric semiconductors with unipolar n-channel performance.
AB - Inspired by the excellent device performance of imide-functionalized polymer semiconductors in organic electronics, a novel imide-based building block, dithienylbenzodiimide (TBDI), with fused backbone is designed and synthesized. Single-crystal structure analysis reveals that the TBDI unit features non-planar backbone conformation but with a tight π-stacking distance of 3.36 Å. By copolymerizing with various electron-rich co-units, a series of TBDI-based polymer semiconductors is synthesized and the optoelectronic, thermal, electrochemical and charge transport properties of the semiconductors are characterized. Attributed to the non-planar backbone and intrinsic electrical property of TBDI, all polymers exhibit wide bandgaps (∼2.0 eV) with low-lying HOMOs (<-5.5 eV). Organic thin-film transistors are fabricated by incorporating the TBDI-based polymers as the active layer to investigate their charge transport properties. The dithienylbenzodiimide-bithiophene copolymer shows ambipolar transport characteristics with an electron and hole mobility of 0.15 and 0.015 cm2 V-1 s-1, respectively. By incorporating weaker electron donor co-units, the dithienylbenzodiimide-thiophene and dithienylbenzodiimide-difluorobithiophene copolymers exhibit unipolar n-channel transistor performance with electron mobility up to 0.11 and 0.34 cm2 V-1 s-1, respectively. Most high-performance n-channel polymer semiconductors reported to date typically show narrow bandgaps with high-lying HOMOs, resulting in substantial p-channel performance. The new TBDI-based wide bandgap polymers with low-lying HOMOs greatly suppress p-channel performance and lead to improved Ion/Ioff ratios. The excellent n-channel performance is attributed to the strong electron-withdrawing capability of imide groups, low-lying frontier molecular orbitals, compact π-stacking distance, and a high degree of film crystallinity as confirmed by GIWAXS analysis with distinct interlamellar and π-stacking diffraction patterns. The result reveals that a building block with non-planar backbone can be utilized for constructing high crystalline polymer semiconductors with substantial charge carrier mobility. The study indicates that dithienylbenzodiimide is a promising unit for synthesizing wide bandgap polymeric semiconductors with unipolar n-channel performance.
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U2 - 10.1039/c7tc02903a
DO - 10.1039/c7tc02903a
M3 - Article
AN - SCOPUS:85030242710
VL - 5
SP - 9559
EP - 9569
JO - Journal of Materials Chemistry C
JF - Journal of Materials Chemistry C
SN - 2050-7526
IS - 37
ER -