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Green-Solvent-Processed Conjugated Polymers for Organic Solar Cells: The Impact of Oligoethylene Glycol Side Chains

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    Green-Solvent-Processed Conjugated Polymers for Organic Solar Cells: The Impact of Oligoethylene Glycol Side Chains
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    • Zheng Chen*
      Zheng Chen
      Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
      Key Laboratory of High-Performance Plastics (Jilin University), Ministry of Education, National & Local Joint Engineering Laboratory for Synthesis Technology of High-Performance Polymer, College of Chemistry, Jilin University, Xiuzheng Road 1788, Changchun 130012, P.R. China
      *Email: [email protected] (Z.C.).
      More by Zheng Chen
    • Liang Yan
      Liang Yan
      Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
      More by Liang Yan
      Orcidhttp://orcid.org/0000-0003-4122-7466
    • Jeromy James Rech
      Jeromy James Rech
      Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
      More by Jeromy James Rech
      Orcidhttp://orcid.org/0000-0001-7963-9357
    • Jun Hu
      Jun Hu
      Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
      More by Jun Hu
    • Qianqian Zhang
      Qianqian Zhang
      Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
      More by Qianqian Zhang
      Orcidhttp://orcid.org/0000-0002-8896-1708
    • Wei You*
      Wei You
      Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
      *Email: [email protected] (W.Y.).
      More by Wei You
      Orcidhttp://orcid.org/0000-0003-0354-1948
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    ACS Applied Polymer Materials

    Cite this: ACS Appl. Polym. Mater. 2019, 1, 4, 804–814
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    https://doi.org/10.1021/acsapm.9b00044
    Published March 8, 2019
    Copyright © 2019 American Chemical Society
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    Abstract

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    Organic photovoltaics (OPVs) possess the advantageous trait of solution processability, yet OPV blends typically use hazardous chlorinated solvents for processing. In order to realize the full advantages of OPVs, as well as growing to an industrial scale, the use of environmentally friendly solvents for processing OPVs needs to be pursued. In this study, we utilized the well-studied polymer PBnDT-FTAZ system as the model conjugated polymer, and synthesized a series of structurally similar conjugated polymers with oligo(ethylene glycol) (OEG) side-chains, aiming to understand the structural requirements to convert conventional conjugated polymers into green-processable alternatives. We elucidated the impact of these OEG chains on the properties of modified polymers when compared with the original PBnDT-FTAZ, including solubility and optoelectronic properties. Finally, aiming to understand the impact of changing side chains to the device performance, we fabricated solar cells with a nonfullerene acceptor (IT-M), achieving decent device efficiencies (over 7%). Additionally, using renewable and green solvent, 2-methyltetrahydrofuran (2-MeTHF), we were able to achieve device efficiencies of over 2%.

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    Supporting Information

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    The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acsapm.9b00044.

    • General methods and equipment; fabrication of OPV devices; detailed synthetic procedure for the monomers and corresponding polymers; NMR spectra and high-resolution mass spectroscopy characterization; UV–vis spectra in solution, thin film, and temperature dependent; TGA curves; cyclic voltammograms and energy diagram; molecular weight information, details, and plot; optical and electrochemical properties of polymers (PDF)

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    Cited By

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    This article is cited by 46 publications.

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    ACS Applied Polymer Materials

    Cite this: ACS Appl. Polym. Mater. 2019, 1, 4, 804–814
    Click to copy citationCitation copied!
    https://doi.org/10.1021/acsapm.9b00044
    Published March 8, 2019
    Copyright © 2019 American Chemical Society
    Request reuse permissions

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