Transient phoretic migration of a permselective colloidal particle

► Compute phoretic velocity of an ion-permselective colloid in unsteady electric field. ► Permselectivity drives bulk concentration polarization. ► Phoretic velocity established on ion diffusion time over the particle. ► Complex, frequency-dependent particle velocity under an AC field. ► Terminal velocity under suddenly applied field approached with long-time tail.