• About
    • Login
    View Item 
    •   Institutional Repository Home
    • Electronic Theses and Dissertations
    • Electronic Theses and Dissertations
    • View Item
    •   Institutional Repository Home
    • Electronic Theses and Dissertations
    • Electronic Theses and Dissertations
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

    All of Institutional RepositoryCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsDepartmentThis CollectionBy Issue DateAuthorsTitlesSubjectsDepartment

    My Account

    LoginRegister

    Influence of Phonon Modes on the Thermal Conductivity of Single-wall, Double-wall, and Functionalized Carbon Nanotubes

    Walker, Ebonee Alexis
    : https://etd.library.vanderbilt.edu/etd-04072012-132301
    http://hdl.handle.net/1803/12045
    : 2012-04-20

    Abstract

    Carbon nanotubes (CNTs) are modeled using the Tersoff-Brenner potential and thermal conductivities were estimated using non-equilibrium molecular dynamics. Thermal conductivity for single-wall carbon nanotubes (SWNTs) and double-wall carbon nanotubes (DWNTs) were studied for lengths from 25 nm to 1 μm. Thermal conductivity increases with length from the inclusion of additional phonon modes. To investigate influences of individual modes on thermal conductivity, DWNTs are used to model vibrational mode confinement in SWNTs. Also, various concentrations of phenyl united atom models and values for the Lennard-Jones parameter σ are used to model functionalization and the influence of bond strength. Thermal conductivity is largely influenced by longitudinal and flexural modes. Due to scattering from phonon-phonon interactions, the combination of the longitudinal and flexural modes results in a lower thermal conductivity than other phonon mode combinations. The influence of suppressing the flexural mode is also observed in the thermal conductivity behavior of functionalized CNTs. When using the united atom model, larger percentages of functionalization result in decreasing flexural modes and, consequently, higher thermal conductivity. Similarly, smaller values of σ, which indicate a stronger bond, showed better thermal conductivity. Overall the best performance resulted from functionalized DWNTs, which have the additional wall to transport energy.
    Show full item record

    Files in this item

    Icon
    Name:
    walker.pdf
    Size:
    1.312Mb
    Format:
    PDF
    View/Open

    This item appears in the following collection(s):

    • Electronic Theses and Dissertations

    Connect with Vanderbilt Libraries

    Your Vanderbilt

    • Alumni
    • Current Students
    • Faculty & Staff
    • International Students
    • Media
    • Parents & Family
    • Prospective Students
    • Researchers
    • Sports Fans
    • Visitors & Neighbors

    Support the Jean and Alexander Heard Libraries

    Support the Library...Give Now

    Gifts to the Libraries support the learning and research needs of the entire Vanderbilt community. Learn more about giving to the Libraries.

    Become a Friend of the Libraries

    Quick Links

    • Hours
    • About
    • Employment
    • Staff Directory
    • Accessibility Services
    • Contact
    • Vanderbilt Home
    • Privacy Policy