Electrical properties and oxide ion conducting mechanism in Na-doped LaPO4

Abstract In this paper, series of Na-doped La1-xNaxPO4-x (0 ≤ x ≤ 0.2) materials are synthesized by solid state reaction method, and single phase has been obtained for 0 ≤ x ≤ 0.1. The doped materials show significantly improved conductivity under dry environment by about four orders of magnitude, but dominated by sodium ion conduction, with ~ 10% oxide ion conduction. The oxide ion conducting mechanism in LaPO4-based materials is studied for the first time by molecular dynamic simulations based on interatomic potential approach. This work therefore provides a comprehensive view of the underlying oxide ion migration mechanism for LaPO4-based materials.