Emerging Abnormal Phenomena in Confined Nanofluidics

Nanofluidics is an emerging field that investigates the properties and transport behavior of fluids confined at the nanometer or even sub-nanometer level. Its development is of great importance for interfacial catalysis, biological science, energy conversion, and other fields. Recent developments in micro-nano processing have allowed the scale of confined channels to be down to the molecular or even atomic level, in which the structure of the molecule or the ion is not negligible. Therefore the confined fluid exhibits properties and behaviors that are different from those of the bulk phase, such as nonlinear transport, Coulomb blockade and ultrafast water transport. In this chapter, we summarize the anomalies of ion, water, and biological molecules under confinement. The first part introduces the current research techniques for confined fluids, followed by discussing the abnormal phenomena of ions, water, and molecules in confined fluids, respectively. Finally, we outline the applications and future challenges of confined nanofluidics.