Abstract
The transport of fluids through nanoscale pores, channels, and membranes has been of great importance in our daily life. Nanoscale transport is relevant to many applications such as agriculture, energy and environmental fields. Considering these applications, it is important to characterize detailed mechanisms of liquid transport through nanoscale defects and pores on surfaces. Such characterization requires a detailed understanding of the deviation of water behavior and its transport mechanisms in nanoscale from bulk water. Molecular dynamics provide proper means to understand the dynamics and mechanisms of motions of water molecules confined in ultra-small spaces. This work examines the water transport through an individual pore which has a nanoscale dimensions ranging from 1.0 to 1.8 nm from molecular dynamics perspective. The effects of the nanopore dimensions as well as the surface wetting properties on the behavior of confined water are studied. The translational and rotational dynamics of water molecules are characterized by examining velocity autocorrelation functions and the calculation of the density of states, which supports the presence of unusual, solid-like behaviors of water molecules. A good understanding of the transport mechanisms and their origins are crucial to address common challenges in many engineering applications such as energy storage and conversion and could pave the way towards more efficient water-energy systems.
