Electrical Circuit Modeling of Nanofluidic Systems

Abstract

Nanofluidic systems exhibit transport characteristics that have made technological marvels such as desalination and energy harvesting possible by virtue of their ability to influence small currents due to selective ion transport. Traditionally, these applications have relied on nanoporous membranes whose complicated geometry impedes a comprehensive understanding of the underlying physics. To bypass the associated difficulties, The authors consider the simpler nanochannel array and elucidate the effects of interchannel interactions on the Ohmic response. It is demonstrated that a nanochannel array is equivalent to an array of mutually independent but identical unit‐cells whereby the array can be represented by an equivalent electrical circuit of resistances connected in a parallel configuration. The model is validated using numerical simulations and experiments. The approach to modeling nanofluidic systems by their equivalent electrical circuit provides an invaluable tool for analyzing and interpreting experimental measurements.

Ion Transport in Multi-Nanochannels Regulated by pH and Ion Concentration

“…The concentration gradient will be destroyed because this EOF will create a vortex in the ion-depleted area, causing the ions to undergo convective mixing. The ion concentration, channel geometry, and strength of the electric field all affect the size and form of electro-convective vortices. − Additionally, the distance between the nanochannels affects the formation of electro-convective vortex zones, which we discuss in the next section.…”

“…Nanochannel arrays have the potential to create quicker and more discriminating molecular sensors. , This study investigated the ion transport properties of nanochannel arrays, wherein the surface charge density of nanochannels is charge-regulated. We examined the impact of different numbers of nanochannels in the array and different distances between adjacent nanochannels on the wall surface charge density, ionic concentration, electric field, and flow field.…”

Beyond power density: unexpected scaling laws in scale up of characterization of reverse-electro-dialysis membranes

“…The access resistances originate from the mismatch between the two section areas S res,k and S membrane (S nano in the original paper), which imposes a convergence/divergence of field lines. There is no simple equation in the general case, but it has been modeled for arbitrary geometries by Green and collaborators 22,24 , and a simple equation has been proposed for an infinite reservoir (S res,k /S membrane → ∞) and a circular nanopore by Hall 25 : R access,assymptotic = 1…”