Silver nanoparticles behave as hydrophobic solutes towards the liquid water structure in the interaction shell. A Raman study in the O-H stretching region

Weak interactions, never reported yet, between silver nanocolloids and water, have been studied by Raman spectroscopy in the O-H stretching region. Subtle interactions regarding the first hydration shell, and perturbing only at a short range the bulk liquid structure of the solvent have been revealed. The interface interactions cause the O-H stretching band of water in the interface layer spectrum to be shifted at higher wavenumbers with respect to the neat water Raman signals. Order/disorder ratio variations, with respect to the liquid spectrum of pure water, are reported.