Over 100 tonnes of separated Pu are stored at Sellafield in the UK as PuO2 powder in sealed steel cans. Under certain circumstances, gas generation may occur in these cans, with consequent pressurization. Many routes to gas production have been suggested, several of which involve complex, inter-connected and poorly understood PuO2/H2O interactions. We are studying these interactions computationally, using DFT within the Hubbard corrected periodic boundary condition (PBC) framework (“GGA+U”) and also employing an embedded cluster approach (the periodic electrostatic embedded cluster method). In this contribution I will report the latest results from both of these approaches, comparing the geometries and energies of water adsoprtion on both stoichiometric and defect low index surfaces. I will also present our calculations of the water desorption temperatures from these surfaces as a function of pressure.

Water adsorption on AnO2 (An = U, Pu) surfaces

253rd National Meeting (2017)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.