Filling the UiO-66 and UiO-66-NH2 metal–organic frameworks with liquid water: A molecular dynamics simulations study

The metal–organic framework UiO-66 has been used to improve membrane performances in water purification and the adsorption of emerging contaminants; however, the process of filling UiO-66 with liquid water has not been studied. This study employs molecular dynamics simulations in NAMD to investigate the filling of dry UiO-66 with liquid water at temperatures between 285 K and 305 K. The filling time, radial distribution functions of water molecules at different sites within UiO-66, root mean square deviation of water molecules, and hydrogen bonding behavior are analyzed. UiO-66- N H 2 is also examined, and simulation results are compared with available experimental data from the literature. Compared to UiO-66- N H 2 , UiO-66 can accommodate more water molecules but exhibits weaker interactions, while the filling process in UiO-66- N H 2 is slightly slower than in UiO-66. • UiO-66 can be filled with approximately 6% more liquid water than UiO-66-NH 2 . • The -NH 2 groups in the linkers enhance water adhesion to the material. • UiO-66 forms hydrogen bonds, primarily through the -OH groups in its clusters.