Centrosymmetric Thiophenemethyleneoxindole‐Based Donor–Acceptor Copolymers for Organic Field‐Effect Transistors

Abstract

Two novel, donor-acceptor-type π-conjugated polymers (P1 and P2) with 3'-(thieno[3,2-b]thiophene-2,5-diylbis(methan-1-yl-1-ylidene))bis-(indolin-2-one) (ITTI) as the acceptor and thiophene/bithiophene as the donor are designed and synthesized by palladium-catalyzed Stille coupling. The optical and electrochemical properties of these polymers are characterized and further implemented into organic field-effect transistors (OFET). Both polymers exhibit excellent thermal stability, broad UV-vis absorption, and high highest occupied molecular orbital energy levels. Thermal annealing induces a well-ordered structure, a highly planar π-system (oxygen-sulfur interaction), and a bathochromic shift in the polymers; furthermore, significant enhancement of the long wavelength intensity is also observed. Both polymers exhibit p-type charge transport behavior, with hole mobilities up to 0.51 cm V s for P1 and 0.65 cm V s for P2. This work demonstrates that ITTI can be a promising building block for the construction of donor-acceptor polymers with high-performance OFETs.

Conjugated Conductive Polymer Materials and its Applications: A Mini-Review

“…In 2018, Zhang et al (2017) reported that introducing hydrogen bonding between the amide and carbonyl into the polymer not only result in polymer self-assembly, but also increases the electron mobility by a factor of 40 compared to its precursor polymer ( Figure 1F ). Recently, Deng et al (2018) introduced S and F atoms to adjust the polymer backbone and obtained a polymer with hole mobility up to 0.65 cm 2 V −1 s −1 . Zhang et al then reported that the main chain coplanarity of polymer semiconductors is more essential than the sole extension of π-conjugation (especially perpendicularly to polymer main chains) after investigating two benzo/naphtodifuranone-based polymers ( Figure 1G ) ( Li et al, 2021 ).…”

Benzo/Naphthodifuranone‐Based Polymers: Effect of Perpendicular‐Extended Main Chain π‐Conjugation on Organic Field‐Effect Transistor Performances

“…[ 11–14 ] Specifically, the backbone structures of CPs, not only has a crucial effect on the intramolecular π‐orbital overlap and delocalization, but also play an important role for enhancing the inter‐(macro)molecular interactions via π–π stacking. [ 15,16 ] Therefore, numerous strategies of tailoring the backbone structures of CPs such as quinoidalization, ladderization, incorporation of non‐covalent interactions, or simply π‐extension of the building blocks within main chains have been applied for the ultimate purpose of delivering high performances in different organic electronic devices. [ 17–20 ]…”

Polymerizations of Diketopyrrolopyrrole-Type Dyes in Unconventional Orientation

“…Density functional theory (DFT) calculations were carried out for the monomers and two repeating units of the polymers, employing a B3LYP/6-31G* basis set with alkyl side chains simplified as a methyl group. , The optimized geometries of the monomers and the polymers are displayed in Figure S14 and Figure S15, respectively, and related dihedral angles data are summarized in Table S2. The DPP-H was a planar structure, and the DPP-B was slightly out of co-planarity because of coordination with boron difluorides.…”