Oxygen transport properties of Ba0.5Sr0.5Co0.8Fe0.2O3−x and Ca0.5Sr0.5Mn0.8Fe0.2O3−x obtained from permeation and conductivity relaxation experiments

Influence of a La0.6Sr0.4CoO3-δ Functional Layer on (Ba0.5Sr0.5)(Co0.8Fe0.2)O3-δ Oxygen Transport Membranes (OTMs)

“…This can be explained by the fact that secondary phases in BSCF tend to form at areas where the ideal cubic lattice is distorted, like grain boundaries or interfaces. (26). While the absolute values for uncoated BSCF at 700 °C are positioned smoothly within the scattering range of both literature data sets, at 600 °C the values presented in this study exceed data from (25) by approx.…”

Oxygen Transport Kinetics of Mixed Ionic-Electronic Conductors by Coupling Focused Ion Beam Tomography and Electrochemical Impedance Spectroscopy

“…[4][5][6][7][8] The ALSmodel is an analytical 1D-model developed for semi-infinite thickness, porous, mixed-conducting cathodes with high ionic-electronic conductivity and no gas phase diffusion limitations. It is generally accepted that for thick cathodes the oxygen surface-exchange and the solid-state diffusion processes are coupled and can be described by the following equation, mathematically equivalent to a Gerischer impedance:…”

“…Many publications have assessed the D and k values of MIEC materials, most commonly by; electrical conductivity relaxation (ECR) measurements for dense bulks [4][5][6][7][8] and temperature for LSCF cathodes. 17 Here it should be pointed out that the well-known ALS model can only be applied if the measured impedance shows a Gerischer impedance, which indicates that the surface-exchange and the oxygen bulk diffusion are strongly coupled.…”

“…[1][2][3] The surface-exchange coefficient (k) and the oxygen diffusion coefficient (D) provide key information about the oxygen transport mechanism that dominates the cathodic ORR. Many publications have assessed the D and k values of MIEC materials, most commonly by; electrical conductivity relaxation (ECR) measurements for dense bulks [4][5][6][7][8] or thin-films 9,10 (k δ , D δ ) and by oxygen tracer diffusion experiments for thin-films 11 or powder 12 (k * , D * ). The oxygen transport parameters are usually determined by ex situ experiments for model systems (i.e.…”

Correlation between thermodynamic and thermomechanical quantities of selected perovskite-type oxides

“…Formation of oxygen vacancies and decreasing oxidation states of B-site cations promote the thermal expansion as well as the oxygen transport properties [13]. Fig.…”