Solution of trivalent cations into uranium dioxide
► Change in solubility limit of sesquioxides in uranium dioxide with excess oxygen. ► Larger trivalent cations found to be soluble regardless of stoichiometry and limit mainly temperature dependent. ► Iron and chromium cation solution limit strongly dependent on stoichiometry, only soluble with exce...
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Published in | Journal of nuclear materials Vol. 420; no. 1; pp. 258 - 261 |
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Main Authors | , , , , , , , |
Format | Journal Article |
Language | English |
Published |
Amsterdam
Elsevier B.V
2012
Elsevier |
Subjects | |
Online Access | Get full text |
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Summary: | ► Change in solubility limit of sesquioxides in uranium dioxide with excess oxygen. ► Larger trivalent cations found to be soluble regardless of stoichiometry and limit mainly temperature dependent. ► Iron and chromium cation solution limit strongly dependent on stoichiometry, only soluble with excess oxygen. ► Addition of trivalent cations removes oxygen excess.
The accommodation of trivalent oxides (M
2O
3) in uranium dioxide has been investigated using atomic scale simulation. Calculations suggest that all trivalent oxides studied preferentially enter UO
2 by associating the substitutional ion with an oxygen vacancy, larger cations forming the cluster
{
2
M
U
′
:
V
O
}
×
. Solution into hyper-stoichiometric UO
2+
x
was accompanied by the formation of the
{
M
U
′
:
U
U
}
×
cluster and smaller solution energies than into stoichiometric UO
2. Solubility is a particularly strong function of hyper-stoichiometry for smaller cations such as Cr
3+, which has implications for the use of Cr
2O
3 as a grain enlarger but not so for larger cations such s Gd
3+. |
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Bibliography: | ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 ObjectType-Article-1 ObjectType-Feature-2 |
ISSN: | 0022-3115 1873-4820 |
DOI: | 10.1016/j.jnucmat.2011.10.006 |