Oxygen Diffusion in Mg-Doped Sm and Gd Zirconates with Pyrochlore Structure
Full article
| Общее |
Language:
Английский,
Genre:
Full article,
Status:
Published,
Source type:
Original
|
| Journal |
Ionics
ISSN: 0947-7047
, E-ISSN: 1862-0760
|
| Output data |
Year: 2020,
Volume: 26,
Number: 9,
Pages: 4621-4633
Pages count
: 13
DOI:
10.1007/s11581-020-03614-5
|
| Tags |
2D diffusion; Diffusion; Isotope exchange of oxygen; Modeling; O conductors; Pyrochlores |
| Authors |
Sadykov Vladislav
1,2
,
Shlyakhtina Anna
3
,
Lyskov Nikolai
4
,
Sadovskaya Ekaterina
1,2
,
Cherepanova Svetlana
1,2
,
Eremeev Nikita
1
,
Skazka Valery
2,5
,
Goncharov Vladimir
1
,
Kharitonova Elena
6
|
| Affiliations |
| 1 |
SB RAS, Federal Research Center Boreskov Institute of Catalysis, Akad. Lavrentieva ave. 5, Novosibirsk 630090, Russia
|
| 2 |
Novosibirsk State University, Pirogova str. 2, Novosibirsk 630090, Russia
|
| 3 |
RAS, N.N. Semenov Federal Research Center for Chemical Physics, Moscow, Russia
|
| 4 |
RAS, Institute of Problems of Chemical Physics, Acad. Semenov ave. 1, Chernogolovka 142432, Russia
|
| 5 |
SB RAS, Sobolev Institute of Mathematics, Acad. Koptyug ave. 4, Novosibirsk 630090, Russia
|
| 6 |
Lomonosov Moscow State University, Leninskiye Gory str. 1/2, Moscow 119991, Russia
|
|
Funding (3)
|
1
|
Russian Science Foundation
|
16-13-00112
|
|
2
|
Federal Agency for Scientific Organizations
|
0303-2016-0013
|
|
3
|
Ministry of Science and Higher Education of the Russian Federation
|
426 (АААА-А20-120013190076-0)
|
Oxides with pyrochlore structure are promising materials for SOFCs, oxygen and hydrogen separation membranes, and other devices. Ln zirconates attract interest due to their oxygen and protonic mobility. In this work, oxygen transport mechanism in Mg-doped Sm and Gd zirconates was studied. Sm1.9Mg0.1Zr2O6.95 and Gd1.9Mg0.1Zr2O6.95 oxides have been prepared via the mechanical activation and characterized by XRD, TGA, and SEM. Oxygen transport features were studied by the oxygen isotope exchange with C18O2. Isotope substitution of bulk oxygen was demonstrated to be described by the 2D diffusion model. Very fast diffusion within grain boundaries provides fast isotope label distribution over the oxide domains, then tracer distributes due to a slower diffusion within domains’ bulk. Three forms of oxygen were distinguished within grains’ bulk. Very fast diffusion along grain boundaries (Dgb ~ 10−7 cm2/s at 700 °C) can provide high rates of oxygen transport in oxygen separation membranes.