Entropic electrokinetics: recirculation, particle separation and negative mobility

Abstract

We show that when particles are suspended in an electrolyte confined between corrugated charged surfaces, electrokinetic flows lead to a new set of phenomena such as particle separation, mixing for low-Reynolds micro- and nano-metric devices and negative mobility. Our analysis shows that such phenomena arise, for incompressible fluids, due to the interplay between the electrostatic double layer and the corrugated geometrical confinement and that they are magnified when the width of the channel is comparable to the Debye length. Our characterization allows us to understand the physical origin of such phenomena therefore shading light on their possible relevance in a wide variety of situations, ranging from nano- and micro-fluidic devices to biological systems.

References in corpus (9)

• Nanofluidics, from bulk to interfaces
• Kinetic Equations for Diffusion in the Presence of Entropic Barriers
• Entropic transport: Kinetics, scaling and control mechanisms
• Rectification in synthetic conical nanopores: a one-dimensional Poisson-Nernst-Planck modeling
• "Blue energy" from ion adsorption and electrode charging in sea- and river water
• Fluid-Structure Interaction in Deformable Microchannels
• Hydrodynamically enforced entropic trapping of Brownian particles
• Confined Brownian ratchets
• Dimer motion on a periodic substrate: Spontaneous symmetry breaking and absolute negative mobility

Cited by in corpus (22)

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• Model microswimmers in channels with varying cross section
• Negative mobility of a Brownian particle: strong damping regime
• Entropically-induced asymmetric passage times of charged tracers across corrugated channels
• Non-monotonous polymer translocation time across corrugated channels: comparison between Fick-Jacobs approximation and numerical simulations
• Generalized Fick Jacobs Approach for describing Adsorption Desorption Kinetics in Irregular Pores under Non Equilibrium Conditions
• Confinement-controlled rectification in a geometric nanofluidic diode
• Flow of colloidal solids and fluids through constrictions: dynamical density functional theory versus simulation
• Giant negative mobility of inertial particles caused by the periodic potential in steady laminar flows
• Driving an electrolyte through a corrugated nanopore
• Anomalous transport in driven periodic systems: distribution of the absolute negative mobility effect in the parameter space
• Working under confinement
• Rectification and non-Gaussian diffusion in heterogeneous media
• Active microrheology in corrugated channels
• Paradoxical nature of negative mobility in the weak dissipation regime
• Spontaneous rectification and absolute negative mobility of inertial Brownian particles induced by Gaussian potentials in steady laminar flows
• Self-generated electrokinetic flows from active-charged boundary patterns
• Turning catalytically active pores into active pumps
• Splitting probabilities for dynamics in corrugated channels: passive VS active Brownian motion
• Local pressure for confined systems
• Mass separation in an asymmetric channel