Active Ionic Fluxes Induce Symmetry Breaking in Charge-Patterned Nanochannels

Biological systems rely on autonomous modes of charge transport to transmit signals. Instead, conventional synthetic systems typically depend on external fields, such as voltage or pressure gradients, to induce transport, which limits their applicability. Here, we investigate nanochannels in which an electrolyte is confined by symmetric boundary patterns combining surface charge and active ionic fluxes. We show that the interplay between diffusion, electrostatics, and hydrodynamics in such nano-confined active-charged systems can trigger symmetry breaking above a critical active flux, leading to directed flow. Our results suggest that active-charged nanochannels can generate net flows of the order of hundreds of millimeters per second, opening pathways toward adaptable ionic devices and neuromorphic architectures.