First-principles molecular dynamics simulations of uranyl ion interaction at the water/rutile TiO2(110) interface

Abstract

The effects of temperature and solvation on uranyl ion adsorption at the water/rutile TiO2(110) interface are investigated by Density Functional Theory (DFT) in both static and Born–Oppenheimer molecular dynamics approaches. According to experimental observations, uranyl ion can form two surface complexes in a pH range from 1.5 to 4.5. Based on these observations, the structures of the complexes at 293K are first calculated in agreement with vacuum static calculations. Then, an increase in temperature (293 to 425K) induces the reinforcement of uranyl ion adsorption due to the release of water molecules from the solvation shell of uranyl ion. Finally, temperature can modify the nature of the surface species.