Oxygen Chemical Diffusion at LaMnO₃ Film/YSZ under Cathodic Polarization by Secondary Ion Mass Spectrometry

Abstract

Oxygen chemical diffusion at La_0.92MnO₃ film/YSZ interface was investigated under cathodic polarized condition. Secondary ion mass spectrometry (SIMS) analysis was performed for the samples with isotope oxygen exchange (¹⁶O/¹⁸O exchange at 1073K). The diffusion profiles of ¹⁸O in the La_0.92MnO₃ film showed that fast ¹⁸O diffusion under cathodic polarization. The active sites for oxygen incorporation were distributed in many spots on YSZ single crystal surface from the SIMS imaging analysis. Also, Mn diffusion from LaMnO₃ to YSZ was observed in many spots on YSZ surface. Oxygen permeation current density through the La_0.92MnO₃ film was calculated by the defect model of LaMnO₃ under cathodic polarization, which was a smaller than the observed value.