TY - JOUR
T1 - Regiochemistry-Driven Organic Electrochemical Transistor Performance Enhancement in Ethylene Glycol-Functionalized Polythiophenes
AU - Hallani, Rawad K.
AU - Paulsen, Bryan D.
AU - Petty, Anthony J.
AU - Sheelamanthula, Rajendar
AU - Moser, Maximilian
AU - Thorley, Karl J.
AU - Sohn, Wonil
AU - Rashid, Reem B.
AU - Savva, Achilleas
AU - Moro, Stefania
AU - Parker, Joseph P.
AU - Drury, Oscar
AU - Alsufyani, Maryam
AU - Neophytou, Marios
AU - Kosco, Jan
AU - Inal, Sahika
AU - Costantini, Giovanni
AU - Rivnay, Jonathan
AU - McCulloch, Iain
N1 - Publisher Copyright:
© 2021 American Chemical Society.
PY - 2021/7/28
Y1 - 2021/7/28
N2 - Novel p-type semiconducting polymers that can facilitate ion penetration, and operate in accumulation mode are much desired in bioelectronics. Glycol side chains have proven to be an efficient method to increase bulk electrochemical doping and optimize aqueous swelling. One early polymer which exemplifies these design approaches was p(g2T-TT), employing a bithiophene-co-thienothiophene backbone with glycol side chains in the 3,3′ positions of the bithiophene repeat unit. In this paper, the analogous regioisomeric polymer, namely pgBTTT, was synthesized by relocating the glycol side chains position on the bithiophene unit of p(g2T-TT) from the 3,3′ to the 4,4′ positions and compared with the original p(g2T-TT). By changing the regio-positioning of the side chains, the planarizing effects of the S-O interactions were redistributed along the backbone, and the influence on the polymer's microstructure organization was investigated using grazing-incidence wide-angle X-ray scattering (GIWAXS) measurements. The newly designed pgBTTT exhibited lower backbone disorder, closer π-stacking, and higher scattering intensity in both the in-plane and out-of-plane GIWAXS measurements. The effect of the improved planarity of pgBTTT manifested as higher hole mobility (μ) of 3.44 ± 0.13 cm2 V-1 s-1. Scanning tunneling microscopy (STM) was in agreement with the GIWAXS measurements and demonstrated, for the first time, that glycol side chains can also facilitate intermolecular interdigitation analogous to that of pBTTT. Electrochemical quartz crystal microbalance with dissipation of energy (eQCM-D) measurements revealed that pgBTTT maintains a more rigid structure than p(g2T-TT) during doping, minimizing molecular packing disruption and maintaining higher hole mobility in operation mode.
AB - Novel p-type semiconducting polymers that can facilitate ion penetration, and operate in accumulation mode are much desired in bioelectronics. Glycol side chains have proven to be an efficient method to increase bulk electrochemical doping and optimize aqueous swelling. One early polymer which exemplifies these design approaches was p(g2T-TT), employing a bithiophene-co-thienothiophene backbone with glycol side chains in the 3,3′ positions of the bithiophene repeat unit. In this paper, the analogous regioisomeric polymer, namely pgBTTT, was synthesized by relocating the glycol side chains position on the bithiophene unit of p(g2T-TT) from the 3,3′ to the 4,4′ positions and compared with the original p(g2T-TT). By changing the regio-positioning of the side chains, the planarizing effects of the S-O interactions were redistributed along the backbone, and the influence on the polymer's microstructure organization was investigated using grazing-incidence wide-angle X-ray scattering (GIWAXS) measurements. The newly designed pgBTTT exhibited lower backbone disorder, closer π-stacking, and higher scattering intensity in both the in-plane and out-of-plane GIWAXS measurements. The effect of the improved planarity of pgBTTT manifested as higher hole mobility (μ) of 3.44 ± 0.13 cm2 V-1 s-1. Scanning tunneling microscopy (STM) was in agreement with the GIWAXS measurements and demonstrated, for the first time, that glycol side chains can also facilitate intermolecular interdigitation analogous to that of pBTTT. Electrochemical quartz crystal microbalance with dissipation of energy (eQCM-D) measurements revealed that pgBTTT maintains a more rigid structure than p(g2T-TT) during doping, minimizing molecular packing disruption and maintaining higher hole mobility in operation mode.
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U2 - 10.1021/jacs.1c03516
DO - 10.1021/jacs.1c03516
M3 - Article
C2 - 34192463
AN - SCOPUS:85110965337
SN - 0002-7863
VL - 143
SP - 11007
EP - 11018
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 29
ER -