Programmable Nanofluidic Memristors Based on Hierarchical Nanochannel/Ionchannel Composite as Artificial Synapses

ABSTRACT Inspired by biological neural signaling, the realization of adaptive neuromorphic computing systems demands iontronic components capable of multimodal switching, yet current nanofluidic devices are typically constrained to a single operational mode. Hierarchical structural design offers a potent route to tailor ion transport properties, harnessing multiscale asymmetry to integrate divergent transport regimes within a unified architecture. Herein, we introduce a hierarchical nanochannel/ionchannel composite (NIC) membrane that fabricated via direct anodic oxidation, which can be served as a robust building block for programmable nanofluidic memristors. We demonstrate that the inherent structural and surface charge asymmetry of the NIC membrane governs ion enrichment/depletion, giving rise to bipolar memristive behavior, while the strong confinement effects within the ionchannel dictate sluggish ion adsorption/desorption kinetics, enabling unipolar memristive behavior. By systematically modulating electrolyte composition and voltage scan rates, we realize a reversible transition between bipolar and unipolar modes. Leveraging these tunable dynamics, we successfully implement various advanced neuromorphic functions. This work reveals the ion transport mechanisms behind nanofluidic memristors, providing scientific guidance for the development of high‐performance neuromorphic devices.