Thermophoresis of Nanodroplets in Deformed Carbon Nanotubes Due to Nanoindentation

Abstract

Carbon nanotubes based on mechanical deformation for controlling mass transport have various promising potential applications in nanofluidic devices. The thermophoresis of water nanodroplets through carbon nanotubes with deformation imposed by nanoindentation is explored using molecular dynamics simulations. We find that deforming the carbon nanotubes can effectively control the thermophoretic motion of the confined droplet. When the carbon nanotubes are deformed to a certain level, the migration of the droplet is significantly limited. Under strong deformation, the exchange of water molecules between separated droplets is blocked by narrow passage. Moreover, we identify some interesting phenomena and important physical mechanisms, and explain them via the relationship between the molecular interactions between the interfacial water and the thermophoretic effect. The thermophoretic dynamics of a small droplet confined in the carbon nanotubes with a larger radius reveals that the interfacial interactions b...