Modulation of Memristive Characteristics by Dynamic Nanoprecipitation inside Conical Nanopores

TL;DR

This paper presents a method to modulate nanofluidic memristors by controlling nanoprecipitate formation inside conical nanopores, enabling stable synapse-like behavior for neuromorphic applications.

Contribution

It introduces a reversible precipitation-based regulation technique to tune memristive behavior in conical nanopores, advancing nanofluidic memristor design.

Findings

Pronounced current hysteresis with CaHPO4 in nanopores.

Memristive behavior depends on salt concentration, voltage, and scan rate.

Stable learning and forgetting processes under pulse voltage stimulation.

Abstract

Nanofluidic memristors have demonstrated great potential for neuromorphic system applications with the advantages of low energy consumption and excellent biocompatibility. Here, an effective way is developed to regulate the memristive behavior of conical nanopores by leveraging the reversible formation and dissolution of nanoprecipitates induced by ion enrichment and depletion in nanopores under opposite voltages. Through the interplay between precipitation dynamics at the pore tip and the ion enrichment/depletion inside the nanopore, conical nanopores exhibit pronounced current hysteresis loops in the presence of CaHPO4, a slightly soluble inorganic salt. The memristive characteristics are found to be strongly dependent on the concentration of CaHPO4, besides the applied voltage amplitude and scan rate. Under the stimulation of pulse voltages, ionic current demonstrates stable learning and forgetting processes with robust switching stability and effective reset capability, which is similar to the short-term plasticity characteristics of biological synapses. Our research may provide a straightforward and tunable approach for the design of nanofluidic memristors.