Ultrafast diffusion of overpressurized gas filled nanobubbles in UO2

Molecular dynamics modeling of diffusion of xenon nanobubbles in UO2 is carried out in this work in a wide range of gas concentrations. For small overpressurized nanobubbles emitted interstitials gather in a cluster near the bubble that significantly accelerates bubble diffusion and lowers its activation energy. This new diffusion mechanism could be a way towards an explanation of contradictory data for UO2 on bubble diffusivity and fission gas release rate. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

In this study, molecular dynamics modeling revealed a new diffusion mechanism for xenon nanobubbles in UO2, which could potentially explain the contradictory data on bubble diffusion and fission gas release rate in UO2.