Transport Properties of Nano-porous Track-etched Membranes in Electrolyte Solutions

Track-etched membranes (TEM) are obtained via irradiation and subsequent etching of thin polymer films. Due to their identical straight cylindrical pores, nano-porous TEMs are suitable for the studies of fundamentals of nano-fluidics. Integrated measurements of salt-rejection, electrokinetic and electrochemical properties of nano-porous TEMs confirm quantitative applicability of standard space-charge model to the description of equilibria and transfer phenomena in nano-pores of ca.20 nm in diameter. In electrolyte mixtures, this same model predicts an interesting phenomenon of strong pressure-driven separation of ions of different mobilities (including very close ones).