  Recent advances in nanofluidics have enabled the confinement of water down to
a single molecular layer. Such monolayer electrolytes show promise in achieving
bio-inspired functionalities through molecular control of ion transport.
However, the understanding of ion dynamics in these systems is still scarce.
Here, we develop an analytical theory, backed up by molecular dynamics
simulations, predicting strongly nonlinear effects in ion transport across
quasi-two-dimensional slits. We show that under an electric field, ions
assemble into elongated clusters, whose slow dynamics result in hysteretic
conduction. This phenomenon, known as memristor effect, can be harnessed to
build an elementary neuron. As a proof-of-concept, we carry out molecular
simulations of two nanofluidic slits reproducing the Hodgkin-Huxley model, and
observe spontaneous emission of voltage spikes characteristic of neuromorphic
activity.
