Dynamic X-ray Spectroscopy of La0.6Sr0.4CoO3-δ Thin Film Electrodes. (10th July 2019)

• Record Type: Journal Article
• Authors: Gerwe, Brian S; Mizuno, Keita; Sekizawa, Oki; Nitta, Kiyofumi; Amezawa, Koji; Adler, Stuart B.
• Is Part Of: ECS transactions. Volume 91:Number 1(2019)
• Page Start: 1387
• Page End: 1395
• Publication Date: 2019-07-10
• Subjects: Electrochemistry -- Periodicals; Electrochemistry; Periodicals; Electronic journals; Electronic journal; 541.37
• DOI: 10.1149/09101.1387ecst
• Languages: English
• ISSNs: 1938-5862

Abstract

Abstract : Dense thin films of the solid oxide fuel cell cathode material La0.6 Sr0.4 CoO3-δ were studied by operando X-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.