Abstract
The interaction between H(2)O and plutonium oxide is an essential aspect of researching plutonium corrosion. We systematically studied the adsorption, dissociation, and diffusion of H(2)O molecules on the PuO(2)(111) surface with the DFT + U-D3 scheme. We find that the top of the Pu atom is the most stable adsorption site for H(2)O molecules on the PuO(2)(111) surface. When multiple H(2)O molecules are adsorbed, hydrogen bonding between molecules can increase the average adsorption energy. H(2)O molecules will dissociate into H atoms and O-H groups under certain conditions. We have paid special attention to the role of hydrogen bonds between H(2)O molecules. When the coverage of H(2)O molecules is low, hydrogen bonds can significantly promote the adsorption and dissociation of H(2)O molecules. And H(2)O tends to exist on the surface of plutonium oxide in dissociated and molecular mixed states. The H atoms produced by the dissociation of H(2)O molecules are not easily diffused, which may be related to the hydrogen bonding between O-H groups. This work has important theoretical significance for deepening the understanding of the corrosion mechanism of plutonium.