Trapping of oxide ions in δ-Bi3YO6

A series of ab initio molecular dynamics (MD) simulations have been performed on the oxide ion conducting solid electrolyte δ-Bi3YO6. The effect of different cationic neighbours on the residence time and occupancy of oxide ion sites was investigated. It was found that sites where neighbouring cations were exclusively bismuth exhibited the lowest residence time and lowest average site occupancy, with these parameters increasing with an increasing number of yttrium cation neighbours. Residence time exhibited Arrhenius type temperature dependence, while the average site occupancies were almost temperature independent. The results are discussed in terms of oxide ion trapping by the dopant cation.