Dynamic process of H-controlled oxygen concentration in LBE: A first-principles study

•The behaviors of H in LBE are investigated.•We clearly explain the dynamic process of the interaction between H and O in LBE.•The equilibrium concentrations of H, H2, HO, O and H2O in LBE at different temperatures are predicted.•The mechanism of H-controlled O concentration in LBE is revealed.

First-principles molecular dynamics simulations have been performed to study the behaviors of H and the dynamic process of H-controlled O concentration in the liquid lead bismuth eutectic (LBE). Our calculations show that H2 molecules in LBE are dissociated to be diffusive H atoms, taking the forms of H-metal clusters. Meanwhile, H prefers to interact with O in LBE to form HO radicals and H2O molecules, reducing the O concentration in LBE. With the mass action analysis, we quantitatively predict the variation of the O concentration in LBE with the amount of the introduced H2 at different temperatures. Our results are practical for the H-controlled O concentration in LBE experiments.