Segregation of Yttrium Ions as {2(Y{sub}Zr)':V{sub}O}{sup}x to the Surfaces of t-ZrO{sub}2

摘要

Atomistic simulation has been used to predict the segregation of defect clusters containing two substitutional Y{sup}(3+) ions and one charge compensating oxygen vacancy to the (100) and (101) surfaces of t-ZrO{sub}2. The most stable orientation of the defect cluster depends on its distance from the surface. Significantly, segregation energies vary greatly between surfaces. For example, the defect cluster is equally stable up to a depth of 9A from the (100) surface but only to a depth of 4A below the (101) surface. In both cases, segregation energies are negligible 12A beneath the surface.