Dynamic X-ray Spectroscopy of La0.6Sr0.4CoO3-δThin Film Electrodes

Autor: Gerwe, Brian S, Mizuno, Keita, Sekizawa, Oki, Nitta, Kiyofumi, Amezawa, Koji, Adler, Stuart B.
Zdroj: ECS Transactions; July 2019, Vol. 91 Issue: 1
Abstrakt: Dense thin films of the solid oxide fuel cell cathode material La0.6Sr0.4CoO3-δwere studied by operandoX-ray absorption spectroscopy under sinusoidal voltage perturbations. This approach showed good agreement with previous steady-state μ-XAS measurements, but with high effective p(O2) resolution over several orders of magnitude. Co oxidation state varied strongest under a 0.5 Hz perturbation suggesting, in agreement with linear impedance, that oxygen exchange kinetics are most active at this timescale. Furthermore, the local structure around Co atoms response varied at different timescales; however, interpretation was limited with only preliminary analysis. Altogether, this approach was shown as a successful step towards developing a technique sensitive to local chemical state that can also separate processes by timescale.
Databáze: Supplemental Index