Determination of Oxygen Content in Pervoskite-Type Cathode Coatings

Abstract

In this paper, La0.75Sr0.25MnO3-δ (LSM) and La0.6Sr0.4CoO3–δ (LSCO)coatings were prepared by the atmospheric plasma spraying method andflame spraying method. Both coatings were annealedat 800 °C, 900 °C, 1000 °C for 5 h, 10h, 15 h and 20 h. Oxygen content of LSM and LSCO coatings weredetermined by redox titration. It is interesting to noted that, oxygen content of LSM and LSCO coatings strongly varied with the annealing temperature andannealing time. The experimental results show that, at same annealingtemperature, oxygen vacancy decreases with the increase of annealing time. For LSM coatings, at 800 °C,the oxygen vacancy, δ, were decreased from 0.419 to 0.353, 0.310 and to 0.258 with theannealing time increased from 5 hto 10 h, 15 h and to 20 h. Under the same annealing time, oxygen vacancydecreased with increase of annealingtemperature. For LSCO coatings, the oxygen vacancy, δ, were decreased from0.698 to 0.573 and to 0.535 after annealed at 800 °C, 900°C and 1000 °C for 5 h.