Diffusive dynamics of charge regulated macro-ion solutions

Abstract

Onsager's variational principle is generalized to address the diffusive dynamics of an electrolyte solution composed of charge-regulated macro-ions and counterions. The free energy entering the Rayleighian corresponds to the Poisson-Boltzmann theory augmented by the charge-regulation mechanism. The dynamical equations obtained by minimizing the Rayleighian include the classical Poisson-Nernst-Planck equations, the Debye-Falkenhagen equation, and their modifications in the presence of charge regulation. By analyzing the steady state, we show that the charge regulation has an important impact on the non-equilibrium macro-ion spatial distribution and their effective charge, deviating significantly from their equilibrium values. Our model, based on Onsager's variational principle offers a unified approach to the diffusive dynamics of electrolytes containing components that undergo various charge association/dissociation processes.

References in corpus (16)

• Theory of Chemical Kinetics and Charge Transfer based on Nonequilibrium Thermodynamics
• Analysis of ionic conductance of carbon nanotubes
• Charge Regulation with Fixed and Mobile Charges
• From solvent free to dilute electrolytes: Essential components for a continuum theory
• Transient dynamics of electric double-layer capacitors: Exact expressions within the Debye-Falkenhagen approximation
• Phase Separation of Polyelectrolytes: The Effect of Charge Regulation
• Charge Regulating Macro-ions in Salt Solutions: Screening Properties and Electrostatic Interactions
• Critical behavior of charge-regulated macro-ions
• Complex Fluids with Mobile Charge-Regulated Macro-Ions
• Onsager's variational principle for nonreciprocal systems with odd elasticity
• Stochastic approach and fluctuation theorem for charge transport in diodes
• Colloid-oil-water-interface interactions in the presence of multiple salts: charge regulation and dynamics
• Dynamic Stern layers in charge-regulating electrokinetic systems: three regimes from an analytical approach
• Counterion-controlled phase equilibria in a charge-regulated polymer solution
• Non-equilibrium steady states of electrolyte interfaces
• Collapse/expansion dynamics and actuation of pH-responsive nanogels