Correlations between crystallographic distributions and mobility of oxide ions in Ba3NbWO8.5

Oxide ion conductors have been a focus of intense research due to their application as electrolytes in solid oxide fuel cells (SOFCs), devices intended to allow the safe utilisation of hydrogen fuel for energy. Ba3NbMoO8.5 is a pure oxide ion conductor with competitive conductivity at "moderate" operating temperatures, but its highly disordered crystal structure is not well understood. We will use single-crystal neutron diffraction to examine the distributions of oxide ions in the structure as Ba3NbMoO8.5 is heated from room temperature to the high temperatures at which it is conductive. By studying the relationship between the oxygen distributions and the metal atom arrangements in this material, we hope to learn how structural features can be tuned to enhance oxide ion conductivity in similar materials.