Electrical Conductance of Nanofluidic Systems subjected to Asymmetric Concentrations

A nanochannel subjected to both a potential and concentration gradient has an asymmetric current-voltage, I-V, response with three primary characteristics: the Ohmic conductance, G, the current at zero voltage, I(v=0), and the voltage at zero current, V(I=0). To date, there is no known self-consistent theory for these characteristics subject to an arbitrary concentration gradient. Here, we present simple expressions for each of these characteristics that have been derived self-consistently. Our findings provide insights into the underlying physics of nanofluidics systems used for water desalination and energy harvesting.