Preparation of stoichiometric and nonstoichiometric magnesium titanate spinels

Wataru Sugimoto, Naohiro Kaneko, Yoshiyuki Sugahara, Kazuyuki Kuroda

    Research output: Contribution to journalArticle

    7 Citations (Scopus)

    Abstract

    Polycrystalline samples of stoichiometric spinels, Mg1+xTi2-xO4 (0≤x≤1.0), and spinels with cation diversity, Mg(1+x)yTi2-xO4 and Mg1+xTi(2-x)y,O4 (x=0.4215, y=0.95-1.05), and oxygen deficiency Mg1+xTi2-xO4-δ (x=0.4215, δ=0.05-0.30) were prepared by solid-state reaction of MgO, TiO2 and Ti to examine the effects of the composition and holding time on the structure of the spinel phase, the impurity phase formation behavior and the electrical properties. In addition to Mg2TiO4 (x=1) prepared at 1300°C under an ambient atmosphere, samples were prepared at 1250°C under an argon atmosphere. Compositional analyses revealed that volatilization of compounds and oxidation during firing were negligible. The variation in the unit cell parameter a of the spinel phase indicated solid-solution formation for all stoichiometric samples in spite of the presence of impurities. The impurity-phase formation behavior was strongly dependent upon synthetic conditions, x-value, and induced nonstoichiometry. Other than the insulating Mg2TiO4, resistivity measurements indicated that all samples were semiconducting below room temperature. No distinct variation in resistivity behavior was observed for samples with different holding time or with induced nonstoichiometry.

    Original languageEnglish
    Pages (from-to)101-105
    Number of pages5
    JournalNippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan
    Volume105
    Issue number2
    Publication statusPublished - 1997

    Fingerprint

    Magnesium
    magnesium
    Impurities
    preparation
    Argon
    impurities
    spinel
    Solid state reactions
    Vaporization
    Cations
    Solid solutions
    Electric properties
    atmospheres
    Positive ions
    electrical resistivity
    vaporizing
    Oxygen
    hypoxia
    Oxidation
    Chemical analysis

    Keywords

    • Electrical properties
    • Magnesium titanate
    • Nonstoichiometry
    • Solid solution
    • Solid-state reaction
    • Spinel structure

    ASJC Scopus subject areas

    • Ceramics and Composites

    Cite this

    @article{adc66a0b98df4a0da511ee7a5047168f,
    title = "Preparation of stoichiometric and nonstoichiometric magnesium titanate spinels",
    abstract = "Polycrystalline samples of stoichiometric spinels, Mg1+xTi2-xO4 (0≤x≤1.0), and spinels with cation diversity, Mg(1+x)yTi2-xO4 and Mg1+xTi(2-x)y,O4 (x=0.4215, y=0.95-1.05), and oxygen deficiency Mg1+xTi2-xO4-δ (x=0.4215, δ=0.05-0.30) were prepared by solid-state reaction of MgO, TiO2 and Ti to examine the effects of the composition and holding time on the structure of the spinel phase, the impurity phase formation behavior and the electrical properties. In addition to Mg2TiO4 (x=1) prepared at 1300°C under an ambient atmosphere, samples were prepared at 1250°C under an argon atmosphere. Compositional analyses revealed that volatilization of compounds and oxidation during firing were negligible. The variation in the unit cell parameter a of the spinel phase indicated solid-solution formation for all stoichiometric samples in spite of the presence of impurities. The impurity-phase formation behavior was strongly dependent upon synthetic conditions, x-value, and induced nonstoichiometry. Other than the insulating Mg2TiO4, resistivity measurements indicated that all samples were semiconducting below room temperature. No distinct variation in resistivity behavior was observed for samples with different holding time or with induced nonstoichiometry.",
    keywords = "Electrical properties, Magnesium titanate, Nonstoichiometry, Solid solution, Solid-state reaction, Spinel structure",
    author = "Wataru Sugimoto and Naohiro Kaneko and Yoshiyuki Sugahara and Kazuyuki Kuroda",
    year = "1997",
    language = "English",
    volume = "105",
    pages = "101--105",
    journal = "Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan",
    issn = "1882-0743",
    publisher = "Ceramic Society of Japan/Nippon Seramikkusu Kyokai",
    number = "2",

    }

    TY - JOUR

    T1 - Preparation of stoichiometric and nonstoichiometric magnesium titanate spinels

    AU - Sugimoto, Wataru

    AU - Kaneko, Naohiro

    AU - Sugahara, Yoshiyuki

    AU - Kuroda, Kazuyuki

    PY - 1997

    Y1 - 1997

    N2 - Polycrystalline samples of stoichiometric spinels, Mg1+xTi2-xO4 (0≤x≤1.0), and spinels with cation diversity, Mg(1+x)yTi2-xO4 and Mg1+xTi(2-x)y,O4 (x=0.4215, y=0.95-1.05), and oxygen deficiency Mg1+xTi2-xO4-δ (x=0.4215, δ=0.05-0.30) were prepared by solid-state reaction of MgO, TiO2 and Ti to examine the effects of the composition and holding time on the structure of the spinel phase, the impurity phase formation behavior and the electrical properties. In addition to Mg2TiO4 (x=1) prepared at 1300°C under an ambient atmosphere, samples were prepared at 1250°C under an argon atmosphere. Compositional analyses revealed that volatilization of compounds and oxidation during firing were negligible. The variation in the unit cell parameter a of the spinel phase indicated solid-solution formation for all stoichiometric samples in spite of the presence of impurities. The impurity-phase formation behavior was strongly dependent upon synthetic conditions, x-value, and induced nonstoichiometry. Other than the insulating Mg2TiO4, resistivity measurements indicated that all samples were semiconducting below room temperature. No distinct variation in resistivity behavior was observed for samples with different holding time or with induced nonstoichiometry.

    AB - Polycrystalline samples of stoichiometric spinels, Mg1+xTi2-xO4 (0≤x≤1.0), and spinels with cation diversity, Mg(1+x)yTi2-xO4 and Mg1+xTi(2-x)y,O4 (x=0.4215, y=0.95-1.05), and oxygen deficiency Mg1+xTi2-xO4-δ (x=0.4215, δ=0.05-0.30) were prepared by solid-state reaction of MgO, TiO2 and Ti to examine the effects of the composition and holding time on the structure of the spinel phase, the impurity phase formation behavior and the electrical properties. In addition to Mg2TiO4 (x=1) prepared at 1300°C under an ambient atmosphere, samples were prepared at 1250°C under an argon atmosphere. Compositional analyses revealed that volatilization of compounds and oxidation during firing were negligible. The variation in the unit cell parameter a of the spinel phase indicated solid-solution formation for all stoichiometric samples in spite of the presence of impurities. The impurity-phase formation behavior was strongly dependent upon synthetic conditions, x-value, and induced nonstoichiometry. Other than the insulating Mg2TiO4, resistivity measurements indicated that all samples were semiconducting below room temperature. No distinct variation in resistivity behavior was observed for samples with different holding time or with induced nonstoichiometry.

    KW - Electrical properties

    KW - Magnesium titanate

    KW - Nonstoichiometry

    KW - Solid solution

    KW - Solid-state reaction

    KW - Spinel structure

    UR - http://www.scopus.com/inward/record.url?scp=0031069365&partnerID=8YFLogxK

    UR - http://www.scopus.com/inward/citedby.url?scp=0031069365&partnerID=8YFLogxK

    M3 - Article

    AN - SCOPUS:0031069365

    VL - 105

    SP - 101

    EP - 105

    JO - Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan

    JF - Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan

    SN - 1882-0743

    IS - 2

    ER -