Direct exfoliation of layered materials in low-boiling point solvents using weak acid salts

Yoshihiko Arao, Jonathon D. Tanks, Masatoshi Kubouchi, Akira Ito, Atsushi Hosoi, Hiroyuki Kawada

    Research output: Contribution to journalArticle

    Abstract

    The method for mass production of nanosheets is essential for fully realizing their commercial use. Direct exfoliation of layered materials in liquid is the simplest and low-cost technique for exfoliation without introducing defects in basal plane. However, the technique requires toxic and high-boiling point solvents, which makes it difficult for further processing. In addition, solvent exchange involves time-consuming processes such as filtering and redispersion. A breakthrough is necessary to make 2D-crystal-based functional dispersions. Here, we find a new method to directly exfoliate layered materials in low-boiling point solvents. Addition of small amounts of salt prevents reaggregation of exfoliated nanosheets and improves electrical repulsion. In this process, the mechanical force applied by sonication generates active carbon species at the fractured surfaces, leading to a reaction between the active carbon and the salt in liquid. High concentration graphene dispersions (1 g/L) can be obtained in isopropanol with only 5 min of sonication. We also confirm salt-assisted exfoliation is effective for the other 2D crystals such as MoS2 and boron nitride in a wide variety of polar solvents. Direct exfoliation in processable solution opens up a range of large-area applications such as high performance nanocomposites and coatings.

    Original languageEnglish
    Pages (from-to)261-268
    Number of pages8
    JournalCarbon
    Volume142
    DOIs
    Publication statusPublished - 2019 Feb 1

    Fingerprint

    Boiling point
    Salts
    Acids
    Sonication
    Nanosheets
    Dispersions
    Carbon
    Crystals
    Graphite
    2-Propanol
    Boron nitride
    Poisons
    Liquids
    Graphene
    Ion exchange
    Nanocomposites
    Coatings
    Defects
    Processing
    Costs

    ASJC Scopus subject areas

    • Chemistry(all)
    • Materials Science(all)

    Cite this

    Direct exfoliation of layered materials in low-boiling point solvents using weak acid salts. / Arao, Yoshihiko; Tanks, Jonathon D.; Kubouchi, Masatoshi; Ito, Akira; Hosoi, Atsushi; Kawada, Hiroyuki.

    In: Carbon, Vol. 142, 01.02.2019, p. 261-268.

    Research output: Contribution to journalArticle

    Arao, Yoshihiko ; Tanks, Jonathon D. ; Kubouchi, Masatoshi ; Ito, Akira ; Hosoi, Atsushi ; Kawada, Hiroyuki. / Direct exfoliation of layered materials in low-boiling point solvents using weak acid salts. In: Carbon. 2019 ; Vol. 142. pp. 261-268.
    @article{72b84b46eafc4dbda655cfad119e3404,
    title = "Direct exfoliation of layered materials in low-boiling point solvents using weak acid salts",
    abstract = "The method for mass production of nanosheets is essential for fully realizing their commercial use. Direct exfoliation of layered materials in liquid is the simplest and low-cost technique for exfoliation without introducing defects in basal plane. However, the technique requires toxic and high-boiling point solvents, which makes it difficult for further processing. In addition, solvent exchange involves time-consuming processes such as filtering and redispersion. A breakthrough is necessary to make 2D-crystal-based functional dispersions. Here, we find a new method to directly exfoliate layered materials in low-boiling point solvents. Addition of small amounts of salt prevents reaggregation of exfoliated nanosheets and improves electrical repulsion. In this process, the mechanical force applied by sonication generates active carbon species at the fractured surfaces, leading to a reaction between the active carbon and the salt in liquid. High concentration graphene dispersions (1 g/L) can be obtained in isopropanol with only 5 min of sonication. We also confirm salt-assisted exfoliation is effective for the other 2D crystals such as MoS2 and boron nitride in a wide variety of polar solvents. Direct exfoliation in processable solution opens up a range of large-area applications such as high performance nanocomposites and coatings.",
    author = "Yoshihiko Arao and Tanks, {Jonathon D.} and Masatoshi Kubouchi and Akira Ito and Atsushi Hosoi and Hiroyuki Kawada",
    year = "2019",
    month = "2",
    day = "1",
    doi = "10.1016/j.carbon.2018.10.063",
    language = "English",
    volume = "142",
    pages = "261--268",
    journal = "Carbon",
    issn = "0008-6223",
    publisher = "Elsevier Limited",

    }

    TY - JOUR

    T1 - Direct exfoliation of layered materials in low-boiling point solvents using weak acid salts

    AU - Arao, Yoshihiko

    AU - Tanks, Jonathon D.

    AU - Kubouchi, Masatoshi

    AU - Ito, Akira

    AU - Hosoi, Atsushi

    AU - Kawada, Hiroyuki

    PY - 2019/2/1

    Y1 - 2019/2/1

    N2 - The method for mass production of nanosheets is essential for fully realizing their commercial use. Direct exfoliation of layered materials in liquid is the simplest and low-cost technique for exfoliation without introducing defects in basal plane. However, the technique requires toxic and high-boiling point solvents, which makes it difficult for further processing. In addition, solvent exchange involves time-consuming processes such as filtering and redispersion. A breakthrough is necessary to make 2D-crystal-based functional dispersions. Here, we find a new method to directly exfoliate layered materials in low-boiling point solvents. Addition of small amounts of salt prevents reaggregation of exfoliated nanosheets and improves electrical repulsion. In this process, the mechanical force applied by sonication generates active carbon species at the fractured surfaces, leading to a reaction between the active carbon and the salt in liquid. High concentration graphene dispersions (1 g/L) can be obtained in isopropanol with only 5 min of sonication. We also confirm salt-assisted exfoliation is effective for the other 2D crystals such as MoS2 and boron nitride in a wide variety of polar solvents. Direct exfoliation in processable solution opens up a range of large-area applications such as high performance nanocomposites and coatings.

    AB - The method for mass production of nanosheets is essential for fully realizing their commercial use. Direct exfoliation of layered materials in liquid is the simplest and low-cost technique for exfoliation without introducing defects in basal plane. However, the technique requires toxic and high-boiling point solvents, which makes it difficult for further processing. In addition, solvent exchange involves time-consuming processes such as filtering and redispersion. A breakthrough is necessary to make 2D-crystal-based functional dispersions. Here, we find a new method to directly exfoliate layered materials in low-boiling point solvents. Addition of small amounts of salt prevents reaggregation of exfoliated nanosheets and improves electrical repulsion. In this process, the mechanical force applied by sonication generates active carbon species at the fractured surfaces, leading to a reaction between the active carbon and the salt in liquid. High concentration graphene dispersions (1 g/L) can be obtained in isopropanol with only 5 min of sonication. We also confirm salt-assisted exfoliation is effective for the other 2D crystals such as MoS2 and boron nitride in a wide variety of polar solvents. Direct exfoliation in processable solution opens up a range of large-area applications such as high performance nanocomposites and coatings.

    UR - http://www.scopus.com/inward/record.url?scp=85055970203&partnerID=8YFLogxK

    UR - http://www.scopus.com/inward/citedby.url?scp=85055970203&partnerID=8YFLogxK

    U2 - 10.1016/j.carbon.2018.10.063

    DO - 10.1016/j.carbon.2018.10.063

    M3 - Article

    VL - 142

    SP - 261

    EP - 268

    JO - Carbon

    JF - Carbon

    SN - 0008-6223

    ER -