Ab Initio Calculations of Pristine and Doped Zirconia Σ5 (310)/[001] Tilt Grain Boundaries

The structure of the cubic‐ZrO 2 symmetrical tilt Σ5 (310)/[001] grain boundary is examined using density functional theory within the local density and pseudopotential approximations. Several pristine stoichiometric grain‐boundary structures are investigated and compared with Z‐contrast scanning transmission electron microscopy and electron energy loss spectroscopy results. The lowest‐energy grain‐boundary structure is found to agree well with the experimental data. When Y 3+ is substituted for Zr 4+ at various sites in the lowest‐energy grain‐boundary structure, the calculations indicate that Y 3+ segregation to the grain boundary is energetically preferred to bulk doping, in agreement with experimental results.