The application of safeguards measures by the International Atomic Energy Agency (IAEA) involves analytical measurements of samples taken during inspections of nuclear facilities. Thus constant development and advancement of analytical techniques is required. For quality control purposes, the IAEA has implemented a dedicated project to enhance its analytical capabilities by producing tailor-made reference materials for the analysis of uranium isotope signatures in (single) particles.
To this end, a particle production set-up was developed and implemented at Forschungszentrum Juelich capable to produce uranium oxide microparticles which are intended to be used as (certified) reference materials for particle analysis methods. A step towards the certification process is the evaluation of consistency of the size distribution and homogeneity. A monodisperse particle size distribution as well as the single phase triuranium octoxide structure was confirmed using SEM, µ-XRD and µ-Raman spectroscopy, respectively. Analysis performed on single uranium oxide microparticles confirmed consistency of the uranium isotopic ratios in comparison to the initial precursor solutions. To improve the homogeneity and particle handling, the particles are transferred into suspensions, for which the stability was investigated with respect to dissolution.