Article

Efficient organic solar cells processed from hydrocarbon solvents

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Abstract

Organic solar cells have desirable properties, including low cost of materials, high-throughput roll-to-roll production, mechanical flexibility and light weight. However, all top-performance devices are at present processed using halogenated solvents, which are environmentally hazardous and would thus require expensive mitigation to contain the hazards. Attempts to process organic solar cells from non-halogenated solvents lead to inferior performance. Overcoming this hurdle, here we present a hydrocarbon-based processing system that is not only more environmentally friendly but also yields cells with power conversion efficiencies of up to 11.7%. Our processing system incorporates the synergistic effects of a hydrocarbon solvent, a novel additive, a suitable choice of polymer side chain, and strong temperature-dependent aggregation of the donor polymer. Our results not only demonstrate a method of producing active layers of organic solar cells in an environmentally friendly way, but also provide important scientific insights that will facilitate further improvement of the morphology and performance of organic solar cells.

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Author information

Author notes

    • Jingbo Zhao
    •  & Yunke Li

    These authors contributed equally to this work.

Affiliations

  1. Department of Chemistry and Energy Institute, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong

    • Jingbo Zhao
    • , Yunke Li
    • , Guofang Yang
    • , Kui Jiang
    • , Haoran Lin
    •  & He Yan
  2. State Key Laboratory for Mechanical Behavior of Materials, Xi’an Jiaotong University, Xi’an 710049, China

    • Guofang Yang
    •  & Wei Ma
  3. HKUST-Shenzhen Research Institute, No. 9 Yuexing 1st Road, Hi-tech Park, Nanshan, Shenzhen 518057, China

    • Kui Jiang
    •  & He Yan
  4. Department of Physics, North Carolina State University, Raleigh, North Carolina 27695, USA

    • Harald Ade

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Contributions

J.Z. selected the solvent/additive and synthesized PffBT4T-C9C13; Y.L. fabricated and optimized the devices; Y.L. prepared the devices for certification and samples for X-ray characterization; W.M. collected the X-ray data; G.Y. analysed the X-ray data supervised by W.M.; K.J. fabricated and optimized the devices based on PTB7 and PffBT4T-C8C12; H.L. synthesized PffT2-FTAZ-C10C14; J.Z., H.Y., W.M. and H.A. integrated the interpretation and drafted the paper; H.Y. conceived and directed the project; all authors commented on the final paper.

Competing interests

The authors declare no competing financial interests.

Corresponding authors

Correspondence to Wei Ma or He Yan.

Supplementary information

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    Supplementary Information

    Supplementary Tables 1-5, Supplementary Figures 1-42, Supplementary Note, Supplementary Methods, Supplementary References.