TY - JOUR
T1 - Rational design of donor-acceptor based semiconducting copolymers with high dielectric constants
AU - Mohapatra, Aiswarya Abhisek
AU - Dong, Yifan
AU - Boregowda, Puttaraju
AU - Mohanty, Ashutosh
AU - Sadhanala, Aditya
AU - Jiao, Xuechen
AU - Narayan, Awadhesh
AU - McNeill, Christopher R.
AU - Durrant, James R.
AU - Patil, Satish
N1 - Funding Information:
A.A.M. thanks Mr. Satya Prakash Yadav for his help in conducting the CV measurements. A.A.M. acknowledges IISc Bangalore for a Senior Research Fellowship. S.P. acknowledge support from the EPSRC project Strategic University Network to Revolutionize Indian Solar Energy-SUNRISE (EP/P032591/1) and the Department of Science and Technology, New Delhi, for a Swarnajayanti Fellowship and SERB, IRHPA grant. This work was performed in part at the SAXS/WAXS beamline at the Australian Synchrotron, part of acknowledges support from the Indian Institute of Science start-up grant (SG/MHRD-19-0001).
Publisher Copyright:
© 2021 American Chemical Society.
Copyright:
Copyright 2021 Elsevier B.V., All rights reserved.
PY - 2021/3/22
Y1 - 2021/3/22
N2 - The low dielectric constant of organic semiconductors limits the efficiency of organic solar cells (OSCs). In an attempt to improve the dielectric constant of conjugated polymers, we report the synthesis of three semiconducting copolymers by combining the thiophene-substituted diketopyrrolopyrrole (TDPP) monomer with three different monomeric units with varying electron donating/accepting strengths: benzodithiophene (BBT-3TEG-TDPP), TDPP (TDPP-3TEG-TDPP), and naphthalene diimide (P(gNDI-TDPP)). Among the series, BBT-3TEG-TDPP and P(gNDI-TDPP) exhibited the highest dielectric constants (∼5) at 1 MHz frequency, signifying the contribution of dipolar polarization from TEG side-chains. Furthermore, transient absorption spectroscopic studies performed on these polymers indicated low exciton diffusion length as observed in common organic semiconducting polymers. Our findings suggest that utilizing the polar side-chains enhances the dielectric constant in a frequency regime of megahertz. However, it is not sufficient to reduce the Coulombic interaction between hole and electron in excitonic solar cells.
AB - The low dielectric constant of organic semiconductors limits the efficiency of organic solar cells (OSCs). In an attempt to improve the dielectric constant of conjugated polymers, we report the synthesis of three semiconducting copolymers by combining the thiophene-substituted diketopyrrolopyrrole (TDPP) monomer with three different monomeric units with varying electron donating/accepting strengths: benzodithiophene (BBT-3TEG-TDPP), TDPP (TDPP-3TEG-TDPP), and naphthalene diimide (P(gNDI-TDPP)). Among the series, BBT-3TEG-TDPP and P(gNDI-TDPP) exhibited the highest dielectric constants (∼5) at 1 MHz frequency, signifying the contribution of dipolar polarization from TEG side-chains. Furthermore, transient absorption spectroscopic studies performed on these polymers indicated low exciton diffusion length as observed in common organic semiconducting polymers. Our findings suggest that utilizing the polar side-chains enhances the dielectric constant in a frequency regime of megahertz. However, it is not sufficient to reduce the Coulombic interaction between hole and electron in excitonic solar cells.
UR - http://www.scopus.com/inward/record.url?scp=85104985432&partnerID=8YFLogxK
U2 - 10.1021/acs.jpcc.1c00340
DO - 10.1021/acs.jpcc.1c00340
M3 - Article
AN - SCOPUS:85104985432
SN - 1932-7447
VL - 125
SP - 6886
EP - 6896
JO - Journal of Physical Chemistry C
JF - Journal of Physical Chemistry C
IS - 12
ER -