Anionic and cationic diffusion in ionic conducting oxides

摘要

This paper concerns an analysis of the transport processes at high temperature in anionic conducting oxides subjected to a chemical potential gradient or an applied electrical field. The general equations are given. The principle of the cationic kinetic demixing under a "generalized" thermodynamical potential gradient is reviewed. Experimental results obtained with yttria-doped zirconia are reported. An experimental procedure for the determination of the oxygen diffusion coefficient in ionic and semiconducting oxides is also described. The results obtained with yttria-stabilized zirconia are compared to both self diffusion and conductivity data. This has allowed us to obtain information concerning the defect structure.