Tunable nanofluidic ion gating via in situ salt precipitation-dissolution

Nanofluidic ion gating underpins both biological signal transduction and iontronic signal processing. However, a simple and reliable mechanism that functions independently of local electrochemical conditions remains unavailable, hindering interference-free integration of artificial iontronic components with biological counterparts. Here, we present a nanofluidic device that enabled ionic gating through pervaporation-driven precipitation and rehydration-driven dissolution (PP&RD) of salt solutions within a nanochannel. Pervaporation induced local salt precipitation in the nanochannel, forming an electrical blockage that suppressed conductance (OFF state), whereas rehydration dissolved the precipitate and restored the conductance (ON state). The ionic gating device exhibited an ON–OFF conductance ratio exceeding 100, fully reversible operation performance, and robust switching across experimental conditions. By integrating two ionic gates in parallel or in series within a single device, we further implement Boolean OR and AND logic operations. PP&RD-based ionic gating thus provided a simple, versatile, and practical foundation for scalable iontronic circuit architecture. Nanofluidic ion gating is crucial for advancing artificial iontronic technologies that can seamlessly integrate with biological systems, yet existing methods often rely on local electrochemical conditions, limiting their scalability and functionality. This study introduces an ionic gating mechanism based on pervaporation-driven precipitation and rehydration-driven dissolution, achieving a high ON–OFF conductance ratio.