Explicit Solution To Extract Self-Diffusion and Surface Exchange Coefficients from Isotope Back-Exchange Experiments

A novel two-step Isotopic Exchange (IE) technique has been developed to investigate the influence of oxygen containing components of ambient air (such as H2O and CO2) on the effective surface exchange coefficient (k*) of a common mixed ionic electronic conductor material.

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Development of a novel SIMS technique for oxygen self-diffusion and surface exchange coefficient measurements in oxides of high diffusivity

Solid State Ionics ◽

10.1016/0167-2738(92)90266-r ◽

1992 ◽

Vol 53-56 ◽

pp. 859-867 ◽

Cited By ~ 120

Author(s):

R.J. Chater ◽

S. Carter ◽

J.A. Kilner ◽

B.C.H. Steele

Keyword(s):

Exchange Coefficient ◽

Surface Exchange ◽

Self Diffusion ◽

Surface Exchange Coefficient

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Nitrogen Self-Diffusion in Polycrystalline Si3N4 Films: Isotope Heterostructures vs. Gas-Exchange

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.237-240.512 ◽

2005 ◽

Vol 237-240 ◽

pp. 512-517 ◽

Cited By ~ 1

Author(s):

Harald Schmidt ◽

Günter Borchardt ◽

Mario Rudolphi ◽

H. Baumann ◽

Michael Bruns ◽

...

Keyword(s):

Mass Spectrometry ◽

Gas Exchange ◽

Activation Enthalpy ◽

Diffusion Mechanism ◽

Exchange Process ◽

Exchange Method ◽

Surface Exchange ◽

Exponential Factor ◽

Temperature Range ◽

Self Diffusion

The self-diffusion of nitrogen is investigated in polycrystalline thin silicon nitride films using a gas-exchange method (14N2/Si3 15N4) in comparison to Si3 14N4/Si3 15N4/Si3 14N4 isotope heterostructures. The films are produced by reactive r. f. magnetron sputtering. Depth profile analysis is carried out with secondary ion mass spectrometry (SIMS), secondary neutral mass spectrometry (SNMS), and nuclear resonant reaction analysis (NRRA). The nitrogen diffusivities determined with the use of isotope heterostructures follow an Arrhenius law in the temperature range between 1200 and 1700 °C with an activation enthalpy of DH = 4.9 eV and a pre-exponential factor of D0 = 1 x 10-6 m2/s, indicating a conventional diffusion mechanism via localized point defects. Using the gas-exchange method, the nitrogen diffusivities could be obtained only in the temperature range between 1600 and 1700 °C. This is due to the fact that at temperatures below 1600 °C the surface exchange process with its high activation enthalpy (about 10 eV) is rate limiting, leading to non detectable diffusion profiles. The application of the different methods of depth profiling leads to the same diffusivities within estimated errors.

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Oxygen self-diffusion and surface exchange studies of oxide electrolytes having the fluorite structure

Solid State Ionics ◽

10.1016/s0167-2738(96)00514-0 ◽

1996 ◽

Vol 93 (1-2) ◽

pp. 125-132 ◽

Cited By ~ 159

Author(s):

P Manning

Keyword(s):

Fluorite Structure ◽

Surface Exchange ◽

Self Diffusion

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Oxygen self-diffusion in cerium oxide doped with Nd

Journal of Materials Research ◽

10.1557/jmr.2001.0029 ◽

2001 ◽

Vol 16 (1) ◽

pp. 179-184 ◽

Cited By ~ 24

Author(s):

Michiyo Kamiya ◽

Eriko Shimada ◽

Yasuro Ikuma ◽

Manabu Komatsu ◽

Hajime Haneda ◽

...

Keyword(s):

Diffusion Coefficient ◽

Oxygen Diffusion ◽

Secondary Ion Mass Spectrometry ◽

Diffusion Annealing ◽

Exchange Coefficient ◽

Surface Exchange ◽

Oxygen Diffusion Coefficient ◽

Self Diffusion ◽

Surface Exchange Coefficient ◽

Secondary Ion

Polycrystalline Ce0.77Nd0.23O1.885having a relative density in excess of 98% was prepared. Oxygen diffusion experiments were performed for the temperature range from 750 to 1100 °C, in an oxygen partial pressure of 6.6 kPa. The concentration profile of18O in the specimens following diffusion annealing was measured by secondary ion mass spectroscopy (SIMS). The oxygen self-diffusion coefficient obtained using secondary ion mass spectrometry was expressed by D = 6.31 × 10−9exp(−53 kJ mol−1/RT) m2s−1and was in the extrinsic region. The oxygen diffusion coefficient of Ce0.77Nd0.23O1.885was larger than that of Ce0.8Y0.2O1.90; it was close to those of Ce0.6Y0.4O1.80and Ce0.69Gd0.31O2−δ. The oxygen diffusion coefficient obtained by the tracer method at 700 °C agreed with that calculated from the electrical conductivity in Ce0.77Nd0.23O1.885. The activation energy of the surface exchange coefficient was 94 kJ mol−1, and the values of the surface exchange coefficient were similar to those of stoichiometric CeO2and ThO2.

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Oxygen Diffusion and Surface Exchange in Yttria-Stabilized Zirconia and Gadolinia-Doped Ceria Ceramics at Low Temperatures

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.289-292.769 ◽

2009 ◽

Vol 289-292 ◽

pp. 769-774 ◽

Cited By ~ 2

Author(s):

Kazimierz Kowalski

Keyword(s):

Low Temperatures ◽

Oxygen Diffusion ◽

Isotopic Labeling ◽

Yttria Stabilized Zirconia ◽

Doped Ceria ◽

Stabilized Zirconia ◽

Surface Exchange ◽

Self Diffusion ◽

Oxygen Surface Exchange ◽

Oxygen Surface

Oxygen self-diffusion and oxygen surface exchange investigations in the yttria-stabilized zirconia (3 and 8 mol% of Y2O3) and in the gadolinia-doped ceria (10 and 20 mol% of Gd2O3) ceramics in the temperature range from 250 to 450°C were performed by means of the 18O isotopic labeling and the SIMS profiling methods. The activation energies of these processes were determined. The results were discussed in comparison with the literature data extrapolated from higher temperatures.

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