Significance Studying water crystallization at low temperature and the lower limit of ice formation is crucial both for a fundamental understanding of water and for practical reasons such as cryopreservation. By taking advantage of the polarized neutron scattering technique and by considering a nanosegregated water–glycerol solution, we are able to characterize the key parameters of ice formation at temperatures near and below the calorimetric glass transition of the solution and provide a general rule for estimating the lower temperature limit of water crystallization in a broad range of aqueous solutions. We also show that nanosegregated water in the glassy solution at low temperature is not in a high-density form but in a low-density one.

Mesoporous materials represent a useful alternative for exploiting the effects of confinement on molecular trapping and catalysis. Their efficiency often depends on the interactions between the surface and the targeted molecules. One way to enhance these interactions is to adjust the hydrophobic/hydrophilic balance of the surface. In the case of mesoporous silica, the incorporation of organic groups is an efficient solution to adapt the material for specific applications. In this work, we have used the co-condensation method to control the hydrophobicity of mesoporous organosilica. The obtained materials are methyl- or phenyl-containing silica with a pore size between 3 and 5 nm. The surface chemistry control has shown the enhanced performance of the materials in two proof-of-concept (PoC) applications: lysozyme adsorption and supported catalysis. The lysozyme adsorption is observed to be over 3 times more efficient with the phenyl-functionalized material than MCM-41, due to π–π interactions. For the catalysis, copper(II) was immobilized on the organosilica surface. In this case, the presence of methyl groups significantly enhanced the product yield for the catalyzed synthesis of a triazole derivative; this was attributed to the enhanced hydrophobic surface–reactant interactions. It was also found that the materials have a higher water adsorption capacity and an improved resistance to hydrolysis. The modulation of water properties in confinement with hydrophobic surfaces, consistently with the water as tuneable solvent (WaTuSo) concept, is a crucial aspect in the efficiency of mesoporous materials for dedicated applications.