Structural incorporation of lanthanides (La, Eu, and Lu) into U3O8 as a function of the ionic radius

Abstract

AbstractThe International Atomic Energy Agency implements safeguard measures to verify the compliance of Member States to their international legal obligations using nuclear material and technology only for peaceful purposes. These safeguard measures, i.a., include analytical measurements of individual micrometer- and submicrometer particles taken by the IAEA on swipe samples during safeguard inspections at nuclear facilities. To ensure the quality control of the analytical results from particle analysis and to further develop mass spectrometric analysis methods, microparticles with well-defined properties as microparticulate reference materials are required. Therefore, mixed lanthanide/uranium oxide microparticles were produced as a first step towards composite reference materials with small amounts of fission products, Pu or Th. A deep understanding of the incorporation mechanisms of dopants into U3O8 structure is essential in this regard. Therefore, bulk-scale comparison materials were produced and doped with lanthanides by co-precipitation methods and systematically investigated by TG, XRD, and Raman. These results will be integrated into the particle production process to design well-defined microparticulate mixed-oxide reference materials. Graphical abstract