Dynamics of Water and Electrolyte Solutions In Porous Silicates: Simulations and Experiments

Quasielastic neutron scattering (QENS) experiments were used to study water and the aqueous solutions of LiCl and CaCl₂ in micro- and mesoporous silicates (MCM 41, SBA 15) over a wide range of thermodynamic conditions from below the water freezing point to above the critical temperature and pressure. The results were interpreted using molecular dynamics simulations and theoretical models, relating water and ion diffusivities to the structure of nanoconfined water in pores of varying sizes and at different salt concentrations. Both pore size and ion concentration were found to have strong influence on the dynamic transitions of water at low temperatures and phase transitions at high temperatures.