Abstract
Water at interfaces differs from bulk water, in both its physical structure and chemical composition. In particular, the role of the termination of the hydrogen-bonded network, the role of charges at interfaces, and the effect of surface charge on water and counterion arrangement have been intensely researched. Advanced surface-specific spectroscopies have contributed substantially to these insights. We have a reasonably good molecular-level understanding of water at interfaces. In contrast, nanoconfined water, and water flowing under non-equilibrium have been much less studied, owing to the challenge of 'seeing' a small number of water molecules under non-equilibrium.
I will show our recent results on the spectroscopy of sub-nanometer confined and flowing water. For water 2D-confined to sub-nanometer dimensions, we observe distinct layering effects. For water flowing along a graphene surface, we find experimental evidence for the recently proposed quantum friction theory.
