American Chemical Society
am0c15538_si_001.pdf (1.28 MB)

Quasi-Stable Salt Gradient and Resistive Switching in Solid-State Nanopores

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journal contribution
posted on 2020-11-18, 08:43 authored by Iat Wai Leong, Makusu Tsutsui, Sanae Murayama, Tomoki Hayashida, Yuhui He, Masateru Taniguchi
Understanding and control of ion transport in a fluidic channel is of crucial importance for iontronics. The present study reports on quasi-stable ionic current characteristics in a SiNx nanopore under a salinity gradient. An intriguing interplay between electro-osmotic flow and local ion density distributions in a solid-state pore is found to induce highly asymmetric ion transport to negative differential resistance behavior under a 100-fold difference in the cross-membrane salt concentrations. Meanwhile, a subtle change in the salinity gradient profile led to observations of resistive switching. This peculiar characteristic was suggested to stem from quasi-stable local ion density around the channel that can be switched between two distinct states via the electro-osmotic flow under voltage control. The present findings may be useful for neuromorphic devices based on micro- and nanofluidic channels.