Strain effects on oxygen transport in tetragonal zirconium dioxide

Xian Ming Bai, Yongfeng Zhang, Michael R. Tonks

    Research output: Contribution to journalArticlepeer-review

    43 Scopus citations

    Abstract

    Temperature accelerated dynamics and molecular dynamics simulations are used to investigate the strain effects on oxygen interstitial and vacancy migration in tetragonal zirconium dioxide. At zero external strain, the anisotropic migration mechanisms of oxygen defects are characterized. At non-zero strains, both the crystal structure and defect migration barriers are modified by strain. Under compressive strains, the defect migration barrier increases with the increasing strain for both interstitials and vacancies. The crystal structure transforms from a tetragonal to a nearly cubic fluorite structure. Accordingly, the defect migration becomes nearly isotropic. Under dilative strains, the migration barrier first decreases then increases with increasing strain for both types of defects. The tetragonal phase transforms to a lower symmetry structure that is close to the orthorhombic phase. In turn, the defect migration becomes highly anisotropic. Under both compressive and dilative strains, interstitials respond to strain more strongly than vacancies. At small dilative strains, an oxygen interstitial has comparable diffusivity to a vacancy, suggesting that both types of defects can contribute to oxygen transport, if they are present. Although currently no previous result is available to validate oxygen interstitial diffusion behavior, the trend of strain effects on oxygen vacancy diffusion is in good agreement with available experimental and theoretical studies in the literature.

    Original languageEnglish (US)
    Pages (from-to)19438-19449
    Number of pages12
    JournalPhysical Chemistry Chemical Physics
    Volume15
    Issue number44
    DOIs
    StatePublished - Nov 28 2013

    All Science Journal Classification (ASJC) codes

    • General Physics and Astronomy
    • Physical and Theoretical Chemistry

    Fingerprint

    Dive into the research topics of 'Strain effects on oxygen transport in tetragonal zirconium dioxide'. Together they form a unique fingerprint.

    Cite this