Oxygen transport at the LaMnO3 film/yttria-stabilized zirconia interface under different cathodic overpotentials by secondary ion mass spectrometry

Oxygen transport under different cathodic overpotentials was investigated a t the LaMnO3 film/Y2O3 stabilized ZrO2 interface. A stable isotope oxygen ( O-18) was adopted as a diffusion marker at 1073 K under cathodic polarizati on, and the quenched samples were analyzed by secondary ion mass spectromet ry. The O-18 diffusion profiles indicate the higher diffusivity of O-18 in LaMnO3 film with the higher cathodic overpotentials. The introduction of ox ygen vacancies by the cathodic polarization can change the diffusion profil es of O-18 in the LaMnO3 film. The diffusion profiles of oxygen in LaMnO3 f ilm under the cathodic polarization were calculated from the literature dat a of oxygen content in LaMnO3 as a first estimation. The calculated diffusi on profiles showed a similar trend with the measured ones, but different co ncentration in the LaMnO3 film under the higher polarization. (C) 2001 The Electrochemical Society.