TY - JOUR
T1 - Effect of Bulky Atom Substitution on Backbone Coplanarity and Electrical Properties of Cyclopentadithiophene-Based Semiconducting Polymers
AU - Park, Sohee
AU - Kim, Yejin
AU - Choi, Changwon
AU - Ahn, Hyungju
AU - Park, Taemin
AU - Lee, Seoung Ho
AU - Jang, Yun Hee
AU - Lee, Byoung Hoon
N1 - Funding Information:
This work was supported by the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT (2019R1C1C1010426, 2019R1A4A1029052, and 2019M3C1B8090804). The device fabrication was partially supported by Nano·Material Technology Development Program through the NRF funded by the Ministry of Science, ICT and Future Planning (2009‐0082580). H.A. would like to give thanks for the support from the NRF funded by Ministry of Science and ICT (NRF‐2020R1F1A1054198).
Publisher Copyright:
© 2021 Wiley-VCH GmbH
PY - 2022/2
Y1 - 2022/2
N2 - The effect of atomic substitution on the optoelectronic properties of a coplanar donor–acceptor (D–A) semiconducting polymer (SPs), prepared using cyclopentadithiophene (CDT) and 2,1,3-benzothiadiazole (BT) moieties, is investigated. By substituting a carbon atom in the BT unit with C-F or C–Cl, two random D–A SPs are prepared, and their optoelectronic properties are thoroughly investigated. Density functional theory calculations demonstrate that the fluorinated polymer has a slightly smaller dihedral angle (ϴ = 0.6°) than the pristine polymer (ϴ = 1.9°) in its lowest-energy conformation, implying efficient charge transport through the coplanar backbone of the fluorinated polymer. However, the chlorinated polymer shows the lowest energy at a relatively larger dihedral angle (ϴ = 139°) due to the steric hindrance induced by bulky chlorine atoms in the backbone, thereby leading to thin-film morphology, which is unfavorable for charge transport. Consequently, the fluorinated polymer yields the highest field-effect mobility (μ) of 0.57 cm2 V−1 s−1, slightly higher than that of the pristine polymer (μ = 0.33 cm2 V−1 s−1), and the extended device lifetime of organic field-effect transistors over 12 d without any encapsulation layers. The results of this study provide design guidelines for air-stable D–A SPs.
AB - The effect of atomic substitution on the optoelectronic properties of a coplanar donor–acceptor (D–A) semiconducting polymer (SPs), prepared using cyclopentadithiophene (CDT) and 2,1,3-benzothiadiazole (BT) moieties, is investigated. By substituting a carbon atom in the BT unit with C-F or C–Cl, two random D–A SPs are prepared, and their optoelectronic properties are thoroughly investigated. Density functional theory calculations demonstrate that the fluorinated polymer has a slightly smaller dihedral angle (ϴ = 0.6°) than the pristine polymer (ϴ = 1.9°) in its lowest-energy conformation, implying efficient charge transport through the coplanar backbone of the fluorinated polymer. However, the chlorinated polymer shows the lowest energy at a relatively larger dihedral angle (ϴ = 139°) due to the steric hindrance induced by bulky chlorine atoms in the backbone, thereby leading to thin-film morphology, which is unfavorable for charge transport. Consequently, the fluorinated polymer yields the highest field-effect mobility (μ) of 0.57 cm2 V−1 s−1, slightly higher than that of the pristine polymer (μ = 0.33 cm2 V−1 s−1), and the extended device lifetime of organic field-effect transistors over 12 d without any encapsulation layers. The results of this study provide design guidelines for air-stable D–A SPs.
KW - chlorination
KW - fluorination
KW - organic field-effect transistors
KW - semiconducting polymers
KW - steric hindrance
UR - http://www.scopus.com/inward/record.url?scp=85119999085&partnerID=8YFLogxK
U2 - 10.1002/marc.202100709
DO - 10.1002/marc.202100709
M3 - Article
C2 - 34792255
AN - SCOPUS:85119999085
SN - 1022-1336
VL - 43
JO - Macromolecular Rapid Communications
JF - Macromolecular Rapid Communications
IS - 4
M1 - 2100709
ER -