Nanoscale water: A Quantum Understanding of Angstrom-scale transport

Water is a substance that needs no introduction: It shapes our blue planet, is life-enabling, and scientifically fascinating with a host of anomalous behaviours. Despite centuries of studies, breakthroughs in the last decade have shown that when wWater is an abundant, yet exceptional and life-enabling substance. The past decades have seen tremendous progress in our understanding of the many peculiarities of water, many of which can be traced to the nature of the interactions between water molecules. When confining water to nanometer-range pores and cavities, wholly new and unexpected phenomena appear: water flows differently in confinement, its phase diagram changes drastically, and conventional theories break down. This is exciting from a scientific perspective, but also of great technological importance: nanoscale water is fundamental to water purification and desalination, where water has to flow through nanopores, and for energy-related processes as a source of protons and hydrogen. Here, we aim for fundamental new scientific insights into water at key length- and time-scales by bringing together a critical mass of researchers with complementarity skillsets in nanofluidics, spectroscopy, and theory and simulation. We follow a radically new perspective for nanoscale water transport, envisioning confined water not only in terms of real-space confinement, but also in terms of its collective modes: how they couple and resonate with the confining material and its - quantum - excitations to affect global transport. Seeing water dynamics in both the real and Fourier worlds allows us to naturally address quantum couplings and light- matter interactions and their effect at nanoscales. This opens a new world of possibilities, e.g., by controlling water motion through fine-tuning of its excitations, quantum engineering of water transport is made possible. Such views have the potential to enable world-changing novel technologies in the water-energy nexus and related fields.