Exploration of the Effects of Particle Size and Mixed Oxidation State on the Stability of CeO2 Nanoparticles
EMSL Project ID
50988
Abstract
Actinide dioxide (AnO2) nanoparticles, a by-product of modern nuclear reactor operation, have been demonstrated to be mobile in the environment. These particles have been shown to have a complex surface chemistry that differs notably from the bulk phase. Actinide dioxides can also adopt non-stoichiometric states as particle size decreases, although the exact nature of the non-stoichiometry is still a subject of debate. Particularly, it has been shown that Pu(IV) in the fluorite PuO2 will disproportionate to either Pu(III) or Pu(V) as nanoparticle size decreases, although the exact nature of this trend has not been identified. Further, due to the hazards of working with actinides, there remains a notable gap in the body of work completed in investigating U, Pu and other transuranium nanoparticles. Therefore, this study uses CeO2 as the surrogate for AnO2. The objective of the study is to establish a relationship between the thermal stability of the AnO2 nanoparticle and its particle size, and knowing the oxidation state distribution, using X-ray photoelectron spectroscopy (XPS), on the surface and in the bulk is crucial for bridging such relationship.
Project Details
Project type
Limited Scope
Start Date
2019-07-08
End Date
2019-09-07
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members
Related Publications
Prieur, Damien, Walter Bonani, Karin Popa, Olaf Walter, Kyle W. Kriegsman, Mark H. Engelhard, Xiaofeng Guo et al. "Size Dependence of Lattice Parameter and Electronic Structure in CeO2 Nanoparticles." Inorganic Chemistry (2020). doi:10.1021/acs.inorgchem.0c00506