A theoretical study of hydrogen atoms adsorption and diffusion on PuO2 (110) surface

作者：Yu H L^*; Tang T; Zheng S T; Shi Y; Qiu R Z; Luo W H; Meng D Q

来源：Journal of Alloys and Compounds, 2016, 666: 287-291.

DOI：10.1016/j.jallcom.2016.01.095

• PuO2 (110) surface
• Hydrogen
• GGA plus U
• cNEB

The mechanisms of adsorption and diffusion of hydrogen atoms on the PuO2 (110) surface are investigated by density functional theory corrected for onsite Coulombic interactions (GGA + U). In order to find out the energetically more favorable adsorption site and optimum diffusion path, adsorption energy of atomic H on various sites and the diffusion energy barrier are derived and compared. Our results show that both chemisorption and physisorption exist for H atoms adsorption configurations on PuO2 (110) surface. Two processes for H diffusion are investigated using the climbing nudged-elastic-band (cNEB) approach. We have identified two diffusion mechanisms, leading to migration of atomic H on the surface and diffusion from surface to subsurface. The energy barriers indicate that it is energetically more favorable for H atom to be on the surface. Hydrogen permeation through purity PuO2 surface is mainly inhibited from hydrogen atom diffusion from surface to subsurface.

• 出版日期2016-5-5
• 单位中国工程物理研究院