Enhanced oxygen diffusion in nano-structured ceria

Abstract

Nano-structured polycrystalline 2 is proposed to be used as a candidate electrolyte material for solid oxide fuel cells (SOFC) operating at temperatures ≤ 600 °С. Here we show that in this material the diffusion activation energy of oxygen ions is 0.35 eV. The diffusion mechanism corresponds to the “single-file” diffusion mechanism, associated with the presence of one-dimensional channels in the anion sublattice of 2. The small grain size of the material ≈ 10 nm, as well as its stoichiometric state (Се2О3), minimize the contribution of the electronic and polaron components of the electrical conductivity of this material, which also contribute to the optimization of SOFC operation.