Size and temperature effects on water dynamics in 10 nm-scale spaces by nmr spectroscopy

We succeeded in filling water into 10 nm-scale spaces and clarifying dynamics of the confined water by using a vapor condensation system, which can control humidity (10-100%) for a long period. From H-1/T ₁ NMR measurements, we found that the molecular motions of the confined water were restricted near surface effects and that the apparent activation energies of confined water decreased with decreasing the sizes. Based on these results, we proposed that adsorbed water molecules having well-ordered structures induce the rearrangement of hydrogen bonding with low activation energy.