  Perovskites with fast oxygen ion conduction can enable technologies like
solid oxide fuel cells. One component of fast oxygen ion conduction is low
oxygen migration barrier. Here we apply ab initio methods on over 40
perovskites to produce a database of oxygen migration barriers ranging from 0.2
to 1.6 eV. Mining the database revealed that systems with low barriers also
have low metal-oxygen bond strength, as measured by oxygen vacancy formation
energy and oxygen p-band center energy. These correlations provide a powerful
descriptor for the development of new oxygen ion conductors and may explain the
poor stability of some of the best oxygen conducting perovskites under reducing
conditions. Other commonly-cited measures of space, volume, or structure
ideality showed only weak correlation with migration barrier. The lowest
migration barriers (< 0.5 eV) belong to perovskites with non-transition-metal
B-site cations, and may require vacancy-creation strategies that involve no
dopants or low-association dopants for optimal performance.
