Multi-interface electrical double layers dynamics as a unified platform for power generation and environmental intelligence

Electrical double layers (EDLs) at solid-liquid interfaces mediate charge separation and ion transport, but their dynamic use for both energy harvesting and sensing in open water remains limited. Here we show that wave-driven multi-interface electrical double layers in a tubular dielectric architecture can couple power generation with environmental perception. Periodic water motion assembles and disrupts coupled inner and outer interfacial layers, producing a charge-relay and parallel-release process that enhances charge transfer and short-circuit current to levels sufficient for low-power sensing. The same ion motion that generates electricity also encodes hydrodynamic and spatial perturbations as current signatures. Inspired by weakly electric fish, we organize these signatures using a main-auxiliary electrode network that amplifies directional responses and enables coating monitoring, wave-state recognition and two-dimensional localization. This work establishes dynamic multi-interface electrical double layers as a physical platform for self-powered hydrospheric sensing and spatially resolved environmental perception. Hydrospheric systems need autonomous power, sensing and protection. Here, the authors show wave-driven electrical double layers generate electricity, enable self-powered corrosion protection and encode coating damage, wave states and spatial cues.