Monoclinic zirconia (m-ZrO2) forms on the internal surface of nuclear fuel Zircaloy cladding, acting as a critical barrier against radionuclide release at the fuel-cladding interface. However, the incorporation of minor actinide elements like americium in m-ZrO2 and resultant structural chemistry remains poorly understood. Using a combination of diffraction and high-resolution X-ray spectroscopic techniques, we have examined m-ZrO2 with 5mol%Am doping. We show Am enters m-ZrO2 tetravalently, where its solubility is approximately 1.0 mol%, m-(Am4+
0.011(7)Zr4+0.989(7))O2, attributed to the large Am4+ cation,where excess Am, that is predominantly trivalent, adopts a C-type (Am4+/3+1-xZr4+x)2O3+x phase in space group Ia-3. The known reversible high temperature phase transformation of m-ZrO2 to tetragonal is further shown to be reduced from 1150 oC to 1050 oC via Am4+ incorporation. The investigation provides critical insight into the chemical reactivity and speciation of minor actinide elements with nuclear fuel cladding related m-ZrO2.
MURPHY Gabriel L.;
GILSON Sara E.;
POPA Karin;
PRIEUR Damien;
SCHENK Sven;
VĂLU Sorin Octavian;
RAMANANTOANINA Harry;
PRUESSMANN Tim;
VITOVA Tonya;
DARDENNE Kathy;
ROTHE Jorg;
COLLE Jean-Yves;
WALTER Olaf;
HUITTINEN N;
2026-02-02
NATURE PORTFOLIO
JRC142845
2399-3669 (online),
https://www.nature.com/articles/s42004-025-01857-9,
https://publications.jrc.ec.europa.eu/repository/handle/JRC142845,
10.1038/s42004-025-01857-9 (online),
| Name | Country | City | Type |
|---|
This document is only visible at the Commission level.
You are not authorized to publish or distribute it outside the European Commission.
This is a public document. You can share this publication.
Datasets
| ID | Title | Public URL |
|---|
Dataset collections
| ID | Acronym | Title | Public URL |
|---|
Scripts / source codes
| Description | Public URL |
|---|
Additional supporting files
| File name | Description | File type |
|---|