Molecular Dynamics Studies of Yttria Stabilized Zirconia. I. Structure and Oxygen Diffusion

The structure and dynamical properties of oxygen conductor yttria stabilized zirconia, (ZrO 2 ) 1- x (Y 2 O 3 ) x , are investigated for three dopant concentrations of 4.85, 10.2 and 22.7 mol%Y 2 O 3 using a method of molecular dynamics simulation. It is shown that a Y–O nearest neighbor distance is longer than that for Zr–O, and an oxygen coordination number for Y ion is a little larger than that for Zr ion in all dopant concentrations. The self-diffusion constant of O ions, D , shows a maximum at 10.2 mol%Y 2 O 3 with increasing the dopant concentration. These results are in agreement with experimental measurements. It is shown that dopant Y ions play an important role in such notable behavior of oxygen diffusion.