No abstract

Zirconia (ZrO 2 )-metal interfaces are interesting for solid oxide fuel cells. Although the oxidation of Pt 3 Zr provides a new route for the formation of ZrO 2 -Pt interfaces, the crystal structure of Pt 3 Zr remains controversial and the oxidation mechanism of Pt 3 Zr is unclear. To solve these problems, we use firstprinciples calculations to explore the crystal structure of Pt 3 Zr. We demonstrate a stable structure of Pt 3 Zr based on phonon dispersion. Importantly, two new Pt 3 Zr structures, Ti 3 Pt-type (Pm 3m) and Fe 3 Al-type (Fm 3m), are predicted. To study the oxidation mechanism, two possible doped models are considered. The calculated results show that the O atom prefers to occupy the tetrahedral interstitial site (TI) in comparison to the octahedral interstitial site (OI). We find that the oxidizing capacity of the Fe 3 Al-type cubic structure is stronger than that of other structures. In particular, we predict that Pt 3 Zr exhibits better oxidation capacity in comparison to other metals because of the strong localized hybridization between Zr and O.