Strong and weak adsorption of CO2 on PuO2 (1Â 1Â 0) surfaces from first principles calculations

The CO2 adsorption on plutonium dioxide (PuO2) (1 1 0) surface was studied using projector-augmented wave (PAW) method based on density-functional theory corrected for onsite Coulombic interactions (GGA + U). It is found that CO2 has several different adsorption features on PuO2 (1 1 0) surface. Both weak and strong adsorptions exist between CO2 and the PuO2 (1 1 0) surface. Further investigation of partial density of states (PDOS) and charge density difference on two typical absorption sites reveal that electrostatic interactions were involved in the weak interactions, while covalent bonding was developed in the strong adsorptions.