Surface-charge-induced alteration of nanovortex patterning in nanoscale confinements with patterned wettability gradients

Abstract

We characterize the generation of flow vortices in nanoscale confinements under the combined effects of patterned surface charge density and substrate wettability. Using molecular dynamics simulations, we elucidate the effects of ion solvation and steric interactions toward influencing the resultant transport characteristics, which are otherwise difficult to resolve using classical electrokinetic theory. We also evaluate the velocity slip (local and global) as well as vorticity parameters, in an effort to assess the implications of the generated flow structure from a pseudocontinuum viewpoint. Results from the present study are expected to provide valuable insights on augmentation of nanoscale mixing.