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Abstract This study introduces a benzodithiophene‐S,S‐tetraoxide (BDTT) monomer as an acceptor and 3,4‐ethylenedioxythiophene flanked thiophene (TEDOT2) and terthiophene (T3) as donor molecules for polymer formation. The synthesis of thepoly(TEDOT2‐BDTT)andpoly(T3‐BDTT)copolymers was performed via a single‐step monomer radical formation that is typically associated with electropolymerization methods. The electropolymerization is controlled by using a suitable monomer stoichiometric ratio that enables the deposition of copolymer thin films on the working electrode. Resultant copolymers were investigated by electrochemical analysis and their electronic properties are discussed in detail. A low average electron transport resistance of 16.5 Ω was found forpoly(TEDOT2‐BDTT), indicating excellent conductive behavior. Solid‐state absorbance and emission studies of the copolymers show visible to near‐infrared spectral activity. Results support an effective strategy towards highly efficient electronically conducting polymers (ECPs) based on a unique BDTT monomer.
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Radically Accessing D–A Type Ambipolar Copolymeric Materials with Intrinsic Electrical Conductivity and Visible–Near Infrared Absorption Via Electro‐Copolymerization
Abstract Thienothiadiazole‐bisthiophene (TTDT2) and diketopyrrolo–pyrrole–bisthiophene (DPPT2) are successfully electro‐copolymerized with terthiophene (T3) as an initiator and linker at low oxidative potentials. AC impedance analysis, absorption spectroscopy, and elemental composition via SEM‐EDX support the formation of donor–acceptor (D–A) type alternating block copolymers, poly(T3‐TTDT2), and poly(T3‐DPPT2). Unique optical properties that span into the near infrared‐II(>1000 nm) region and inherent electrical conductivity at the p‐type regime, n‐type regime, and in between the two regimes (i.e., typical insulator region) are observed. This study showcases the advantages of electro‐polymerization toward tailoring of next generation opto‐electronic materials.
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- Award ID(s):
- 1757220
- PAR ID:
- 10459720
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Macromolecular Chemistry and Physics
- Volume:
- 220
- Issue:
- 21
- ISSN:
- 1022-1352
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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