The PhD project will seek to investigate, experimentally and computationally, the corrosion mechanism(s), including intermediates, products and reaction rates, of spent nuclear fuel (SNF) in oxidative environments. The objective is therefore, to be able to predict quantitatively the degree of corrosion and product formation as a function of time and temperature by using a combination of experimental techniques (fluorescence, Raman, EXAFS) and computational techniques (density functional theory, DFT). The focus will be on understanding the surface chemistry of nuclear fuel, modelling the formation and dissolution of the surface oxides exposed to wet environments.
Hubbard-corrected density functional theory (DFT+U) and dynamical mean-field theory (DMFT) will be employed to provide an accurate description of structure and electronic properties of the material surface and the reactive species, predict the geometry and energetics of the local and global minima as well as the activation energies for reactions occurring on the surface of the materials investigated. Experimental validation will allow us to calibrate and benchmark the theoretical results against state-of-the-art measurements including laser fluorescence and Raman spectroscopy, as well as X-ray spectroscopy at synchrotron facilities (EXAFS). The project will also benefit from parallel experimental work at the University of Bristol (Scott/Springell), capable of supplying single-crystal thin films of U phases with a precisely defined surface orientation.
Academic Lead: David Read
Researcher: Joshua Bright
Location: University of Surrey