Electro-Induced Dewetting and Concomitant Ionic Current Avalanche in Nanopores

Abstract

Electrically driven ionic transport of room-temperature ionic liquids (RTILs) through nanopores is studied using atomistic simulations. The results show that in nanopores wetted by RTILs a gradual <i>dewetting</i> transition occurs upon increasing the applied voltage, which is accompanied by a sharp <i>increase</i> in ionic current. These phenomena originate from the solvent-free nature of RTILs and are in stark contrast with the transport of conventional electrolytes through nanopores. Amplification is possible by controlling the properties of the nanopore and RTILs, and we show that it is especially pronounced in charged nanopores. The results highlight the unique physics of nonequilibrium transport of RTILs in confined geometries and point to potential experimental approaches for manipulating ionic transport in nanopores, which can benefit diverse techniques including nanofluidic circuitry and nanopore analytics