Enhanced thermoelectric power factor in Yb1-xSc xAl2 alloys using chemical pressure tuning of the Yb valence

Gloria J. Lehr, Donald T. Morelli, Hyungyu Jin, Joseph P. Heremans

    Research output: Research - peer-reviewArticle

    • 7 Citations

    Abstract

    We have investigated the influence of Sc substitution on the transport and magnetic properties of YbAl2, a well-known intermediate valence compound. Sc substitution provides a chemical pressure that decreases the lattice constant and thereby alters the Yb valence as a function of composition and temperature. We observe a strong correlation between the Seebeck coefficient and the ratio of trivalent to divalent Yb in these compounds, as determined from magnetic susceptibility measurements. This correlation indicates that the largest absolute value of the Seebeck coefficient is achieved when the average Yb valence is near 2.5 (the ratio of divalent to trivalent Yb is 1:1). It is shown that Sc concentration can be used as a means to tune both the magnitude of the maximum of the Seebeck coefficient and the temperature at which this absolute maximum occurs, improving the prospects of the use of these materials in cryogenic Peltier coolers.

    LanguageEnglish (US)
    Article number223712
    JournalJournal of Applied Physics
    Volume114
    Issue number22
    DOIs
    StatePublished - Dec 14 2013

    Profile

    Seebeck effect
    tuning
    valence
    substitutes
    temperature
    coolers
    cryogenics
    transport properties
    magnetic properties
    magnetic permeability

    ASJC Scopus subject areas

    • Physics and Astronomy(all)

    Cite this

    Enhanced thermoelectric power factor in Yb1-xSc xAl2 alloys using chemical pressure tuning of the Yb valence. / Lehr, Gloria J.; Morelli, Donald T.; Jin, Hyungyu; Heremans, Joseph P.

    In: Journal of Applied Physics, Vol. 114, No. 22, 223712, 14.12.2013.

    Research output: Research - peer-reviewArticle

    @article{5f2605627b2243bcb87a2fa6f1253915,
    title = "Enhanced thermoelectric power factor in Yb1-xSc xAl2 alloys using chemical pressure tuning of the Yb valence",
    abstract = "We have investigated the influence of Sc substitution on the transport and magnetic properties of YbAl2, a well-known intermediate valence compound. Sc substitution provides a chemical pressure that decreases the lattice constant and thereby alters the Yb valence as a function of composition and temperature. We observe a strong correlation between the Seebeck coefficient and the ratio of trivalent to divalent Yb in these compounds, as determined from magnetic susceptibility measurements. This correlation indicates that the largest absolute value of the Seebeck coefficient is achieved when the average Yb valence is near 2.5 (the ratio of divalent to trivalent Yb is 1:1). It is shown that Sc concentration can be used as a means to tune both the magnitude of the maximum of the Seebeck coefficient and the temperature at which this absolute maximum occurs, improving the prospects of the use of these materials in cryogenic Peltier coolers.",
    author = "Lehr, {Gloria J.} and Morelli, {Donald T.} and Hyungyu Jin and Heremans, {Joseph P.}",
    year = "2013",
    month = "12",
    doi = "10.1063/1.4842795",
    volume = "114",
    journal = "Journal of Applied Physics",
    issn = "0021-8979",
    publisher = "American Institute of Physics Publising LLC",
    number = "22",

    }

    TY - JOUR

    T1 - Enhanced thermoelectric power factor in Yb1-xSc xAl2 alloys using chemical pressure tuning of the Yb valence

    AU - Lehr,Gloria J.

    AU - Morelli,Donald T.

    AU - Jin,Hyungyu

    AU - Heremans,Joseph P.

    PY - 2013/12/14

    Y1 - 2013/12/14

    N2 - We have investigated the influence of Sc substitution on the transport and magnetic properties of YbAl2, a well-known intermediate valence compound. Sc substitution provides a chemical pressure that decreases the lattice constant and thereby alters the Yb valence as a function of composition and temperature. We observe a strong correlation between the Seebeck coefficient and the ratio of trivalent to divalent Yb in these compounds, as determined from magnetic susceptibility measurements. This correlation indicates that the largest absolute value of the Seebeck coefficient is achieved when the average Yb valence is near 2.5 (the ratio of divalent to trivalent Yb is 1:1). It is shown that Sc concentration can be used as a means to tune both the magnitude of the maximum of the Seebeck coefficient and the temperature at which this absolute maximum occurs, improving the prospects of the use of these materials in cryogenic Peltier coolers.

    AB - We have investigated the influence of Sc substitution on the transport and magnetic properties of YbAl2, a well-known intermediate valence compound. Sc substitution provides a chemical pressure that decreases the lattice constant and thereby alters the Yb valence as a function of composition and temperature. We observe a strong correlation between the Seebeck coefficient and the ratio of trivalent to divalent Yb in these compounds, as determined from magnetic susceptibility measurements. This correlation indicates that the largest absolute value of the Seebeck coefficient is achieved when the average Yb valence is near 2.5 (the ratio of divalent to trivalent Yb is 1:1). It is shown that Sc concentration can be used as a means to tune both the magnitude of the maximum of the Seebeck coefficient and the temperature at which this absolute maximum occurs, improving the prospects of the use of these materials in cryogenic Peltier coolers.

    UR - http://www.scopus.com/inward/record.url?scp=84890473326&partnerID=8YFLogxK

    UR - http://www.scopus.com/inward/citedby.url?scp=84890473326&partnerID=8YFLogxK

    U2 - 10.1063/1.4842795

    DO - 10.1063/1.4842795

    M3 - Article

    VL - 114

    JO - Journal of Applied Physics

    T2 - Journal of Applied Physics

    JF - Journal of Applied Physics

    SN - 0021-8979

    IS - 22

    M1 - 223712

    ER -