TY - JOUR
T1 - Impact of Oligoether Side-Chain Length on the Thermoelectric Properties of a Polar Polythiophene
AU - Craighero, Mariavittoria
AU - Guo, Jiali
AU - Zokaei, Sepideh
AU - Griggs, Sophie
AU - Tian, Junfu
AU - Asatryan, Jesika
AU - Kimpel, Joost
AU - Kroon, Renee
AU - Xu, Kai
AU - Reparaz, Juan Sebastian
AU - Martín, Jaime
AU - McCulloch, Iain
AU - Campoy-Quiles, Mariano
AU - Müller, Christian
N1 - Publisher Copyright:
© 2023 The Authors. Published by American Chemical Society
PY - 2024/5/28
Y1 - 2024/5/28
N2 - Conjugated polymers with oligoether side chains make up a promising class of thermoelectric materials. In this work, the impact of the side-chain length on the thermoelectric and mechanical properties of polythiophenes is investigated. Polymers with tri-, tetra-, or hexaethylene glycol side chains are compared, and the shortest length is found to result in thin films with the highest degree of order upon doping with the p-dopant 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ). As a result, a stiff material with an electrical conductivity of up to 830 ± 15 S cm-1 is obtained, resulting in a thermoelectric power factor of about 21 μW m-1 K-2 in the case of as-cast films. Aging at ambient conditions results in an initial decrease in thermoelectric properties but then yields a highly stable performance for at least 3 months, with values of about 200 S cm-1 and 5 μW m-1 K-2. Evidently, identification of the optimal side-chain length is an important criterion for the design of conjugated polymers for organic thermoelectrics.
AB - Conjugated polymers with oligoether side chains make up a promising class of thermoelectric materials. In this work, the impact of the side-chain length on the thermoelectric and mechanical properties of polythiophenes is investigated. Polymers with tri-, tetra-, or hexaethylene glycol side chains are compared, and the shortest length is found to result in thin films with the highest degree of order upon doping with the p-dopant 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ). As a result, a stiff material with an electrical conductivity of up to 830 ± 15 S cm-1 is obtained, resulting in a thermoelectric power factor of about 21 μW m-1 K-2 in the case of as-cast films. Aging at ambient conditions results in an initial decrease in thermoelectric properties but then yields a highly stable performance for at least 3 months, with values of about 200 S cm-1 and 5 μW m-1 K-2. Evidently, identification of the optimal side-chain length is an important criterion for the design of conjugated polymers for organic thermoelectrics.
KW - chemical doping
KW - conjugated polymer
KW - electrical conductivity
KW - organic thermoelectrics
KW - side-chain length
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U2 - 10.1021/acsaelm.3c00936
DO - 10.1021/acsaelm.3c00936
M3 - Review article
C2 - 38828039
AN - SCOPUS:85175076802
SN - 2637-6113
VL - 6
SP - 2909
EP - 2916
JO - ACS Applied Electronic Materials
JF - ACS Applied Electronic Materials
IS - 5
ER -