Water Confined in Mesoporous TiO 2 Aerosols: Insights from NMR Experiments and Molecular Dynamics Simulations

VELASCO, MANUEL I.; FRANZONI, M. BELÉN; FRANCESCHINI, ESTEBAN A.; GONZALEZ SOLVEYRA, ESTEFANÍA; SCHERLIS, DAMIÁN; ACOSTA, RODOLFO H.; SOLER-ILLIA, GALO J. A. A.

JOURNAL OF PHYSICAL CHEMISTRY C

AMER CHEMICAL SOC

Lugar: Washington; Año: 2017 vol. 121 p. 7533 - 7541

1932-7447

The adsorption of water vapor in mesoporous TiO2 was studied by Nuclear magneticResonance (NMR) and multi-scale Molecular Dynamics simulations. Three differentwater environments were distinguished and quantified: a first layer, where stronglybound water molecules exist at the inner surfaces; a second less structuredlayer, but still with restricted mobility; and a bulk-like fraction of mobilewater. The obtained NMR results can be explained in the framework of moleculardynamics simulations that give insight on the filling mechanisms in TiO2 nanoporousmaterials. For these highly hydrophilic materials, it is shown that adsorptionisotherms may render a smaller effective pore size due to the presence of alayer of highly bound water.