Synthesis and Redox Behavior of a Sheathed Cross-Conjugated Polythiophene

Control over the electronic structure in π-conjugated polymers is of great importance for the development of organic electronics and spintronics. In this study, we synthesized a sheathed cross-conjugated polythiophene through oxidative electrochemical polymerization. Spectroelectrochemistry has revealed that unlike linearly conjugated polythiophenes, polarons were confined in the repeating units that were segmented by cross-conjugation.

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Identifying the "true" repeat unit of a copolymer using time-resolved electron paramagnetic resonance spectroscopy: a case study involving PNDIT2, NDI-T2 and T-NDI-T

10.26434/chemrxiv-2022-jwv10 ◽

2022 ◽

Author(s):

Clemens Matt ◽

Rukiya Matsidik ◽

Deborah L. Meyer ◽

Mirjam Schröder ◽

Michael Sommer ◽

...

Keyword(s):

Electron Paramagnetic Resonance ◽

Electronic Structure ◽

Conjugated Polymers ◽

Organic Electronics ◽

Repeat Unit ◽

Paramagnetic Resonance ◽

Time Resolved ◽

Donor And Acceptor ◽

The Impact ◽

Electron Paramagnetic

Semiconducting polymers promise to revolutionise the way electronic devices can be built and deployed for a vast array of applications ranging from light-energy conversion to sensors to thermoelectric generators. Conjugated push-pull copolymers consisting of alternating donor and acceptor moieties are at the heart of these applications, due to the large tunability of their electronic structure. Hence, knowing the repeat unit and thus the chromophore of these materials is essential for a detailed understanding of the structure--function relationship of conjugated polymers used in organic electronics applications. Therefore, spectroscopic tools providing the necessary molecular resolution that allows to discriminate between different building blocks and to decide which one actually resembles the electronic structure of the polymer are of utmost importance. Time-resolved electron paramagnetic resonance (TREPR) spectroscopy is both, perfectly suited for this task and clearly superior to optical spectroscopy, particularly when supported by quantum-chemical calculations. This is due to its molecular resolution and unique capability of using light-induced triplet states to probe the electronic structure as well as the impact of the local environment. Here, we demonstrate the power of this approach for the polymer PNDIT2 (poly{[N,N'-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5'-(2,2'-bithiophene)}) revealing NDI-T2 unambiguously as the "true" repeat unit of the polymer, representing the chromophore. The alternative building block T-NDI-T has a markedly different electronic structure. These results are of high importance for the rational design of conjugated polymers for organic electronics applications.

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Electronic structure studies of conducting polymers by electron energy-loss spectroscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163265 ◽

1996 ◽

Vol 54 ◽

pp. 160-161

Author(s):

J. Fink

Keyword(s):

Electronic Structure ◽

Conducting Polymers ◽

Conjugated Polymers ◽

Electron Acceptors ◽

Electron Donors ◽

Light Emitting ◽

One Dimensional ◽

New Class ◽

Electrical Conductivities ◽

Electron Energy Loss

Conducting polymers comprises a new class of materials achieving electrical conductivities which rival those of the best metals. The parent compounds (conjugated polymers) are quasi-one-dimensional semiconductors. These polymers can be doped by electron acceptors or electron donors. The prototype of these materials is polyacetylene (PA). There are various other conjugated polymers such as polyparaphenylene, polyphenylenevinylene, polypoyrrole or polythiophene. The doped systems, i.e. the conducting polymers, have intersting potential technological applications such as replacement of conventional metals in electronic shielding and antistatic equipment, rechargable batteries, and flexible light emitting diodes.Although these systems have been investigated almost 20 years, the electronic structure of the doped metallic systems is not clear and even the reason for the gap in undoped semiconducting systems is under discussion.

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Tuning the Electronic Structure and Solubility of Conjugated Polymers with Perfluoroalkyl Substituents: Poly(3-perfluorooctylthiophene), the First Supercritical CO2-soluble Conjugated Polymer

Advanced Materials ◽

10.1002/adma.200305333 ◽

2004 ◽

Vol 16 (2) ◽

pp. 180-183 ◽

Cited By ~ 44

Author(s):

L. Li ◽

K. E. Counts ◽

S. Kurosawa ◽

A. S. Teja ◽

D. M. Collard

Keyword(s):

Electronic Structure ◽

Conjugated Polymers ◽

Conjugated Polymer ◽

Supercritical Co2

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Light-Emitting Diodes Based on Conjugated Polymers: Control of Colour and Efficiency

MRS Proceedings ◽

10.1557/proc-247-647 ◽

1992 ◽

Vol 247 ◽

Cited By ~ 62

Author(s):

Paul L. Burn ◽

A. B. Holmes ◽

A. Kraft ◽

A. R. Brown ◽

D. D. C. Bradley ◽

...

Keyword(s):

Electronic Structure ◽

Conjugated Polymers ◽

Light Emitting Diodes ◽

Fold Increase ◽

Transport Layer ◽

Electron Transport Layer ◽

Metal Contacts ◽

Light Emitting ◽

Lithographic Patterning ◽

Energy Gaps

ABSTRACTStudies of the effect of different electrode combinations on the device characteristics of simple three layer light-emitting diodes (LEDs) prepared with poly(ρ-phenylenevinylene) (PPV) as the emissive layer sandwiched between two metal contacts have shown that it is generally more difficult to inject electrons than holes. In order to improve the efficiency of such devices it is, therefore, necessary to develop methods to enhance the injection of electrons and we illustrate here one example where we have successfully achieved this by the introduction of a further, electron transport, layer. The result is an eight fold increase in efficiency over our best three layer PPV devices. The efficiency is also dependent on the details of the polymer electronic structure and using a family of copolymers we have been able to produce enhancements in efficiency to values of up to 30 times that of the corresponding PPV devices. Variations in the polymer electronic structure also affect the colour of emission and the same family of copolymers allow control of emission colour from blue/green to orange/red. Supramolecular control of the copolymer electronic structure can be achieved by lithographic patterning and we show that it is possible to produce regions within a single polymer film that possess different π-π* energy gaps.

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Electrochemical polymerization for two-dimensional conjugated polymers

Journal of Materials Chemistry C ◽

10.1039/c8tc04149k ◽

2018 ◽

Vol 6 (40) ◽

pp. 10672-10686 ◽

Cited By ~ 15

Author(s):

Qing Zhang ◽

Huanli Dong ◽

Wenping Hu

Keyword(s):

Conjugated Polymers ◽

Electrochemical Polymerization ◽

Research Progress ◽

Future Research ◽

Special Focus ◽

Two Dimensional ◽

Research Directions ◽

Potential Applications ◽

Future Research Directions ◽

Recent Research Progress

This article places special focus on the recent research progress of the EP method in synthesizing CPs. In particular, their potential applications as 2D CPs are summarized, with a basic introduction of the EP method, its use in synthesizing CPs as well as the promising applications of the obtained CPs in different fields. Discussions of current challenges in this field and future research directions are also given.

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