% IMPORTANT: The following is UTF-8 encoded. This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.
@ARTICLE{Heidenreich:278811,
author = {Heidenreich, M. and Kaps, Ch. and Simon, A. and
Schulze-Küppers, F. and Baumann, S.},
title = {{E}xpansion behaviour of ({G}d, {P}r)-substituted
{C}e{O}$_{2}$ in dependence on temperature and oxygen
partial pressure},
journal = {Solid state ionics},
volume = {283},
issn = {0167-2738},
address = {Amsterdam [u.a.]},
publisher = {Elsevier Science},
reportid = {FZJ-2015-07038},
pages = {56-67},
year = {2015},
abstract = {Substituted ceria is a material which has attracted great
interest in solid oxide fuel cell technology [45]. Due to
its chemical stability, it may also be a promising candidate
as a mixed conductive membrane for oxygen separation with
flue gas contact. As part of this paper, dilatometry
measurements and X-ray powder diffraction experiments were
carried out on ceramic materials in air and in argon with
two separate series involving the substitution of ceria;
cerium was substituted with different amounts of Gd and Pr.
The first substitution of Gd caused an increase of the unit
cell with a small rise in linear thermal expansion in
relation to pure ceria. CeO2 − δ and Ce0.8Gd0.2O2 − δ
showed no chemical expansion in both atmospheres. The second
substitution of Gd with Pr decreased the unit cell in
relation to pure ceria. It is therefore understandable that
Pr is preferentially introduced and shown in this work as
Pr4 + in ceria. These samples showed a remarkable chemical
expansion in air and in argon. The chemical expansion
displayed a clear positive correlation with increasing Pr
content. The thermal expansion coefficients are comparable
to the first substitution without any trend in relation to
the amount of Pr. The dilatometry behaviour above 400 °C
can be explained due to the release of oxygen and
simultaneous reduction of Pr4 +, forming Pr3 + and oxygen
vacancies. The results are in accordance with the two
competing processes of forming vacancies (lattice
contraction) and ionic radius change (lattice expansion)
[16] and [27]. After cooling in air, the samples showed no
residual expansion. In contrast, these samples displayed a
remarkable residual expansion in argon of about $0.87\%$ of
the total relative expansion of $1.85\%$ for Ce0.8Pr0.2O2
− δ},
cin = {IEK-1},
ddc = {530},
cid = {I:(DE-Juel1)IEK-1-20101013},
pnm = {113 - Methods and Concepts for Material Development
(POF3-113)},
pid = {G:(DE-HGF)POF3-113},
typ = {PUB:(DE-HGF)16},
UT = {WOS:000367113100008},
doi = {10.1016/j.ssi.2015.11.001},
url = {https://juser.fz-juelich.de/record/278811},
}