Figure 5. Surface effects on water diffusion.

Diffusion coefficients of water in MFI zeolites from experiments (dots) and model (triangles) with increasing concentration of hydrophilic defects. Self-diffusivity (D, red triangles) is obtained from MD simulations, averaged in the adsorption range and rescaled by the experimental self-diffusivity of bulk water at 300 K (see Supplementary Fig. 9). Corrected diffusivities are obtained by either considering the effect of surface barriers on MD results by equation (4) (, blue triangles, where α=5.0 × 10⁻⁹ m s⁻¹ is assumed as constant and equal to the experimental value found for silicalite-1) or by experiments (D_eff/Γ, black dots; see Fig. 4 and Supplementary Fig. 2 in ref. 27).