A study of diffusion behavior of elements lanthanum and oxygen in Mo–La 2O 3 cathode

Abstract

The diffusion behavior of elements lanthanum and oxygen in Mo–La 2O 3 cathode has been carried out by using Auger Electron Spectroscopy. Lanthanum and oxygen ions (La 3+ and O 2+) diffuse from the grain boundaries to the surface. The experimental results were analyzed by kinetics of grain boundary diffusion. In the temperature range 1123 K–1423 K, the diffusion coefficients of La 3+ and O 2+ ions were found to fit with the following expression: D La =3.6703×10 −16 exp(−1.01639×10 5/ RT) m 2 s −1 D O =1.5122×10 −16 exp(−8.13066×10 4/ RT) m 2 s −1