Surface Oxygen Exchange Kinetics in Oxide-Ion Conducting Solids

AbstractThe surface oxygen exchange on oxides with high oxygen ion mobility is modelled with a two step reaction with adsorbed mono-atomic oxygen species as intermediate. Interpretation of the Po2 dependence of the exchange rates, following from this model, indicates that these adsorbed oxygen atoms are singly charged.For the stabilized δ-Bi2O3 solid electrolyte a good agreement has been found between the isotope exchange model and the electrochemical study of the oxygen exchange using gold electrodes. For the mixed La-Sr cobaltite perovskite a change in the surface exchange reaction is observed going from room temperature to 600°C. Indications are that above 450°C the bulk exchange is rate limiting with a (Po2)−1 dependence while below this temperature it is assumed that the dissociative adsorption is rate limiting with a (Po2)1/2 dependence.

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Effect of grain boundaries in La0.84Sr0.16CoO3−δ on oxygen diffusivity and surface exchange kinetics

Physical Chemistry Chemical Physics ◽

10.1039/d1cp01099a ◽

2021 ◽

Author(s):

Natalia Porotnikova ◽

Andrei Farlenkov ◽

Sergey Naumov ◽

Maxim Vlasov ◽

Anna Khodimchuk ◽

...

Keyword(s):

Single Crystal ◽

Grain Boundaries ◽

Gas Phase ◽

Oxygen Exchange ◽

Polycrystalline Specimen ◽

Surface Exchange ◽

Oxygen Diffusivity ◽

Exchange Kinetics ◽

Oriented Single Crystal

The 16O/18O oxygen exchange kinetics between the gas phase and the oriented single crystal and polycrystalline specimen has been studied; the rates of individual stages of oxygen exchange have been calculated and discussed.

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Surface Oxygen Exchange Kinetics of Solid Oxide Ion Conductors

Fast Ion Transport in Solids ◽

10.1007/978-94-011-1916-0_9 ◽

1993 ◽

pp. 167-180 ◽

Cited By ~ 1

Author(s):

B. A. Boukamp ◽

I. C. Vinke ◽

K. J. Vries ◽

A. J. Burggraaf

Keyword(s):

Oxygen Exchange ◽

Solid Oxide ◽

Surface Oxygen ◽

Exchange Kinetics ◽

Kinetics Of ◽

Oxide Ion Conductors ◽

Oxide Ion ◽

Ion Conductors

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Fast Oxygen Ion Diffusion and Surface Exchange Kinetics in the Oxides LnBaCo2O5+x (Ln = Pr, Nd) with Perovskite Related Structures and Ordered A Cations.

ECS Meeting Abstracts ◽

10.1149/ma2005-02/22/836 ◽

2005 ◽

Keyword(s):

Ion Diffusion ◽

Surface Exchange ◽

Oxygen Ion ◽

Exchange Kinetics ◽

Oxygen Ion Diffusion

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Oxygen surface exchange kinetics of Ba0.5Sr0.5Co0.8Fe0.2O3−δ

Physical Chemistry Chemical Physics ◽

10.1039/c9cp06650k ◽

2020 ◽

Vol 22 (18) ◽

pp. 10158-10169

Author(s):

V. A. Eremin ◽

M. V. Ananyev ◽

H. J. M. Bouwmeester ◽

E. Kh. Kurumchin ◽

Ch.-Y. Yoo

Keyword(s):

Gas Phase ◽

Oxygen Exchange ◽

Oxide Surface ◽

Surface Exchange ◽

Exchange Kinetics ◽

Kinetics Of ◽

Oxygen Surface Exchange ◽

Oxygen Surface

The mechanism of oxygen exchange between the gas phase and Ba0.5Sr0.5Co0.8Fe0.2O3−δ oxide was evaluated by considering the inhomogeneity of the oxide surface.

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The effect of water vapor on surface oxygen exchange kinetics of thin film (La,Sr)(Co,Fe)O3-δ

Journal of Power Sources ◽

10.1016/j.jpowsour.2019.227478 ◽

2020 ◽

Vol 451 ◽

pp. 227478

Author(s):

Dongwei Xu ◽

E. Mitchell Hopper ◽

Kee-Chul Chang ◽

Peter M. Baldo ◽

Haesun Park ◽

...

Keyword(s):

Thin Film ◽

Water Vapor ◽

Oxygen Exchange ◽

Surface Oxygen ◽

Effect Of Water ◽

Exchange Kinetics ◽

Kinetics Of

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Is the surface oxygen exchange rate linked to bulk ion diffusivity in mixed conducting Ruddlesden–Popper phases?

Faraday Discussions ◽

10.1039/c5fd00014a ◽

2015 ◽

Vol 182 ◽

pp. 113-127 ◽

Cited By ~ 10

Author(s):

Alex C. Tomkiewicz ◽

Mazin A. Tamimi ◽

Ashfia Huq ◽

Steven McIntosh

Keyword(s):

Exchange Rate ◽

Exchange Rates ◽

Ion Mobility ◽

Surface Composition ◽

Large Body ◽

High Sensitivity ◽

Oxygen Exchange ◽

Surface Oxygen ◽

Ion Scattering ◽

Surface Exchange

The possible link between oxygen surface exchange rate and bulk oxygen anion diffusivity in mixed ionic and electronic conducting oxides is a topic of great interest and debate. While a large body of experimental evidence and theoretical analyses support a link, observed differences between bulk and surface composition of these materials are hard to reconcile with this observation. This is further compounded by potential problems with simultaneous measurement of both parameters. Here we utilize separate techniques, in situ neutron diffraction and pulsed isotopic surface exchange, to examine bulk ion mobility and surface oxygen exchange rates of three Ruddlesden–Popper phases, general form An−1A′2BnO3n+1, An−1A′2BnX3n+1; LaSrCo0.5Fe0.5O4−δ (n = 1), La0.3Sr2.7CoFeO7−δ (n = 2) and LaSr3Co1.5Fe1.5O10−δ (n = 3). These measurements are complemented by surface composition determination via high sensitivity-low energy ion scattering. We observe a correlation between bulk ion mobility and surface exchange rate between materials. The surface exchange rates vary by more than one order of magnitude with high anion mobility in the bulk of an oxygen vacancy-rich n = 2 Ruddlesden–Popper material correlating with rapid oxygen exchange. This is in contrast with the similar surface exchange rates which we may expect due to similar surface compositions across all three samples. We conclude that experimental limitations lead to inherent convolution of surface and bulk rates, and that surface exchange steps are not likely to be rate limiting in oxygen incorporation.

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