Polonium speciation by XAFS technique: Bridging fundamental research with environmental safety – XAFS-PO

Polonium, discovered by Marie and Pierre Curie in 1898, has received increasing attention due to its pronounced toxicity and prevalence in environmental matrices around historic uranium mining sites. In addition, its predicted significant production in lead-bismuth cooled fast neutron reactors implies its potential environmental and health impacts. There is an urgent need for a comprehensive understanding of the chemical behaviour of polonium in various environments. The XAFS-PO project aims to fill the gap in our understanding of the fundamental chemistry of polonium, which is currently characterized by ambiguity and conflicting views, particularly in the identification of polonium species in solutions. Using X-ray Absorption Fine Structure (XAFS) spectroscopy - a sophisticated technique that provides insights at the molecular level - this project will study three key polonium species: 1) polonium in highly concentrated HCl medium, 2) Po(IV) species at pH 5-8 without complexing agents, and 3) Po(IV) species at pH 5-8 complexed with a selected organic molecule. By combining the artificial production of polonium isotopes from the cyclotron, the separation and sample preparation by radioanalytical techniques, and the XAFS analysis in the MARS beamline at SOLEIL synchrotron, we aim to provide ground-breaking insights into the identification of polonium species, setting the stage for future studies and security measures.