Modification of TiO2 nanoparticles with oleyl phosphate via phase transfer in the toluene−water system and application of modified nanoparticles to cyclo-olefin-polymer-based organic−inorganic hybrid films exhibiting high refractive indices

Shiori Takahashi, Shuhei Hotta, Akira Watanabe, Naokazu Idota, Kimihiro Matsukawa, Yoshiyuki Sugahara

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    4 Citations (Scopus)

    Abstract

    Oleyl-phosphate-modified TiO2 nanoparticles (OP_TiO2) were prepared via phase transfer from an aqueous phase containing dispersed TiO2 nanoparticles to a toluene phase containing oleyl phosphate (OP, a mixture of monoester and diester), and employed for the preparation of OP_TiO2/ cyclo-olefin polymer (COP) hybrid films with high-refractive indices. The modification of TiO2 by OP was essentially completed by reaction at room temperature for 8 h, and essentially all the TiO2 nanoparticles in the aqueous phase were transferred to the toluene phase. The infrared and solid-state 13C cross-polarization and magic-angle spinning (CP/ MAS) NMR spectrum of OP_TiO2 showed the presence of oleyl groups originating from oleyl phosphate. The solid-state 31P MAS NMR spectrum of OP_TiO2 exhibited new signals at −1.4, 2.1, and 4.8 ppm, indicating the formation of Ti−O−P bonds. CHN and inductively coupled plasma analyses revealed that the major species bound to the TiO2 surface was tridentate CH3(CH2)7CHCH(CH2)8P(OTi)3. These results clearly indicate that the surfaces of the TiO2 nanoparticles were modified by OP moieties via phase transfer. OP_TiO2/COP hybrid films exhibited excellent optical transparency up to 19.1 vol % TiO2 loading, and the light transmittance of the hybrid films with 19.1 vol % TiO2 loading was 99.8% at 633 nm. The refractive index of these hybrid films rose to 1.83.

    Original languageEnglish
    Pages (from-to)1907-1912
    Number of pages6
    JournalACS Applied Materials and Interfaces
    Volume9
    Issue number2
    DOIs
    Publication statusPublished - 2017 Jan 1

    Fingerprint

    Alkenes
    Olefins
    Refractive index
    Polymers
    Phosphates
    Nanoparticles
    Toluene
    Nuclear magnetic resonance
    Magic angle spinning
    Inductively coupled plasma
    Transparency
    Polarization
    Infrared radiation

    Keywords

    • Cyclo-olefin polymer
    • Oleyl phosphate
    • Organic−inorganic hybrid
    • Phase transfer
    • Refractive index
    • Surface modification
    • TiO2 nanoparticle

    ASJC Scopus subject areas

    • Materials Science(all)

    Cite this

    @article{cdade19f8bbb4a01ad3ab41f1724ff51,
    title = "Modification of TiO2 nanoparticles with oleyl phosphate via phase transfer in the toluene−water system and application of modified nanoparticles to cyclo-olefin-polymer-based organic−inorganic hybrid films exhibiting high refractive indices",
    abstract = "Oleyl-phosphate-modified TiO2 nanoparticles (OP_TiO2) were prepared via phase transfer from an aqueous phase containing dispersed TiO2 nanoparticles to a toluene phase containing oleyl phosphate (OP, a mixture of monoester and diester), and employed for the preparation of OP_TiO2/ cyclo-olefin polymer (COP) hybrid films with high-refractive indices. The modification of TiO2 by OP was essentially completed by reaction at room temperature for 8 h, and essentially all the TiO2 nanoparticles in the aqueous phase were transferred to the toluene phase. The infrared and solid-state 13C cross-polarization and magic-angle spinning (CP/ MAS) NMR spectrum of OP_TiO2 showed the presence of oleyl groups originating from oleyl phosphate. The solid-state 31P MAS NMR spectrum of OP_TiO2 exhibited new signals at −1.4, 2.1, and 4.8 ppm, indicating the formation of Ti−O−P bonds. CHN and inductively coupled plasma analyses revealed that the major species bound to the TiO2 surface was tridentate CH3(CH2)7CHCH(CH2)8P(OTi)3. These results clearly indicate that the surfaces of the TiO2 nanoparticles were modified by OP moieties via phase transfer. OP_TiO2/COP hybrid films exhibited excellent optical transparency up to 19.1 vol {\%} TiO2 loading, and the light transmittance of the hybrid films with 19.1 vol {\%} TiO2 loading was 99.8{\%} at 633 nm. The refractive index of these hybrid films rose to 1.83.",
    keywords = "Cyclo-olefin polymer, Oleyl phosphate, Organic−inorganic hybrid, Phase transfer, Refractive index, Surface modification, TiO2 nanoparticle",
    author = "Shiori Takahashi and Shuhei Hotta and Akira Watanabe and Naokazu Idota and Kimihiro Matsukawa and Yoshiyuki Sugahara",
    year = "2017",
    month = "1",
    day = "1",
    doi = "10.1021/acsami.6b13208",
    language = "English",
    volume = "9",
    pages = "1907--1912",
    journal = "ACS applied materials & interfaces",
    issn = "1944-8244",
    publisher = "American Chemical Society",
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    }

    TY - JOUR

    T1 - Modification of TiO2 nanoparticles with oleyl phosphate via phase transfer in the toluene−water system and application of modified nanoparticles to cyclo-olefin-polymer-based organic−inorganic hybrid films exhibiting high refractive indices

    AU - Takahashi, Shiori

    AU - Hotta, Shuhei

    AU - Watanabe, Akira

    AU - Idota, Naokazu

    AU - Matsukawa, Kimihiro

    AU - Sugahara, Yoshiyuki

    PY - 2017/1/1

    Y1 - 2017/1/1

    N2 - Oleyl-phosphate-modified TiO2 nanoparticles (OP_TiO2) were prepared via phase transfer from an aqueous phase containing dispersed TiO2 nanoparticles to a toluene phase containing oleyl phosphate (OP, a mixture of monoester and diester), and employed for the preparation of OP_TiO2/ cyclo-olefin polymer (COP) hybrid films with high-refractive indices. The modification of TiO2 by OP was essentially completed by reaction at room temperature for 8 h, and essentially all the TiO2 nanoparticles in the aqueous phase were transferred to the toluene phase. The infrared and solid-state 13C cross-polarization and magic-angle spinning (CP/ MAS) NMR spectrum of OP_TiO2 showed the presence of oleyl groups originating from oleyl phosphate. The solid-state 31P MAS NMR spectrum of OP_TiO2 exhibited new signals at −1.4, 2.1, and 4.8 ppm, indicating the formation of Ti−O−P bonds. CHN and inductively coupled plasma analyses revealed that the major species bound to the TiO2 surface was tridentate CH3(CH2)7CHCH(CH2)8P(OTi)3. These results clearly indicate that the surfaces of the TiO2 nanoparticles were modified by OP moieties via phase transfer. OP_TiO2/COP hybrid films exhibited excellent optical transparency up to 19.1 vol % TiO2 loading, and the light transmittance of the hybrid films with 19.1 vol % TiO2 loading was 99.8% at 633 nm. The refractive index of these hybrid films rose to 1.83.

    AB - Oleyl-phosphate-modified TiO2 nanoparticles (OP_TiO2) were prepared via phase transfer from an aqueous phase containing dispersed TiO2 nanoparticles to a toluene phase containing oleyl phosphate (OP, a mixture of monoester and diester), and employed for the preparation of OP_TiO2/ cyclo-olefin polymer (COP) hybrid films with high-refractive indices. The modification of TiO2 by OP was essentially completed by reaction at room temperature for 8 h, and essentially all the TiO2 nanoparticles in the aqueous phase were transferred to the toluene phase. The infrared and solid-state 13C cross-polarization and magic-angle spinning (CP/ MAS) NMR spectrum of OP_TiO2 showed the presence of oleyl groups originating from oleyl phosphate. The solid-state 31P MAS NMR spectrum of OP_TiO2 exhibited new signals at −1.4, 2.1, and 4.8 ppm, indicating the formation of Ti−O−P bonds. CHN and inductively coupled plasma analyses revealed that the major species bound to the TiO2 surface was tridentate CH3(CH2)7CHCH(CH2)8P(OTi)3. These results clearly indicate that the surfaces of the TiO2 nanoparticles were modified by OP moieties via phase transfer. OP_TiO2/COP hybrid films exhibited excellent optical transparency up to 19.1 vol % TiO2 loading, and the light transmittance of the hybrid films with 19.1 vol % TiO2 loading was 99.8% at 633 nm. The refractive index of these hybrid films rose to 1.83.

    KW - Cyclo-olefin polymer

    KW - Oleyl phosphate

    KW - Organic−inorganic hybrid

    KW - Phase transfer

    KW - Refractive index

    KW - Surface modification

    KW - TiO2 nanoparticle

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    U2 - 10.1021/acsami.6b13208

    DO - 10.1021/acsami.6b13208

    M3 - Article

    AN - SCOPUS:85035208473

    VL - 9

    SP - 1907

    EP - 1912

    JO - ACS applied materials & interfaces

    JF - ACS applied materials & interfaces

    SN - 1944-8244

    IS - 2

    ER -