Effect of the Debye Screening Parameter and Electrolyte Valence On the Transport of Ions In Nanochannels

We examine the effects of electrolyte valence, concentration and pH on the current transport through nanopores in synthetic membranes in the case when the Electric Double Layer (EDL) thicknesses are comparable with dimensions of the nanopores in the membranes. The pores were fabricated by irradiation of the foils with swift heavy ions and subsequent chemical etching. Electrical conductivity measurements showed that the nanopores in the membrane are cation selective and rectify the current with the preferential direction. We present a theoretical and experimental account of the effects of the thicknesses of the electric double layer and pore surface charge on the ionic transport in the nanopores. The analysis leads to better fundamental understanding of the electrical interactions between the fixed and mobile charges of within the nanopore.