Probing the pore space in mesoporous materials by laser enhanced hyperpolarised 129Xe NMR
Résumé
Laser hyperpolarised (HP) 129Xe NMR technique has been used to study the porous structure of ordered purely siliceous MCM-41, SBA-15 and functionalised mesoporous materials and mesoporous SiO2 thin films. The use of hyperpolarised xenon allows us to measure spectra at very low concentrations of xenon where xenon reflects mainly interaction between the adsorbed xenon atoms and the surface. Variable temperature measurements allowed us to obtain information on the heat of adsorption of xenon on the surface and to evaluate the chemical shift of xenon interacting with the surface.