Katie Wellstead

Future reactor designs such as DEMO and STEP will breed large quantities of tritium fuel and maintaining tritium inventory is essential to safe and efficient plant operation. Thin (micron-scale) multilayer coatings are one way to control tritium diffusion. Erbium oxide barriers provide significant permeation reduction, however, experimental measurements quantifying this protection in the literature can vary and are often orders of magnitude lower than theoretical predictions, making it difficult to accurately validate coating performance. A key reason for this is a limited understanding of hydrogen isotope trapping and transport behaviour within ceramic coatings, which could be addressed through quantification and spatial mapping of hydrogen isotopes within the coating and at the coating-substrate interface. My project applies the high spatial resolution and chemical sensitivity of APT to erbium oxide coatings; address the knowledge gap around hydrogen isotope transport and trapping in ceramic oxides, with the ultimate aim of improving coating lifetime predictions.