Investigation of Unique Protonic and Hydrodynamic Behavior of Aqueous Solutions Confined in Extended Nanospaces

Abstract

AbstractStudies on novel devices utilizing characteristics of confined geometries have attracted much attention. In particular, a 10–1,000 nm space (extended nanospace) has been expected to establish superior chemical analysis systems in liquid phases, because it not only bridges the methodological gap between conventional nanotechnology and microfluidic technology, but also the scientific one between single molecules and the bulk condensed phase. Therefore, engineering, fluidics, and chemistry concerned with extended nanospaces have been investigated, and unique physicochemical phenomena in the spaces have been clarified. In this review, we summarize recent research outcomes about protonic and hydrodynamic properties of liquids confined in extended nanospaces. Furthermore, we assume a novel molecular description, composed of the electric double layer (EDL) model and the three‐phase model, consisting of adsorbed, proton transfer, and bulk phases, to explain the unique properties induced by the extended nanospace confinement. Finally, the device applications using extended nanospaces are introduced and their potentials are discussed.