A method to tune the ionic current rectification of track-etched nanopores by using surfactant

Phys Chem Chem Phys. 2011 Jan 14;13(2):576-81. doi: 10.1039/c0cp00587h. Epub 2010 Nov 1.

Abstract

A method is reported here to tune the ionic current rectification behavior through a conical nanopore fabricated with the track-etching technique. In order to change the surface charge property of the pore wall, we added the cationic surfactant hexadecyl trimethylammonium bromide (CTAB) into the working electrolyte of 0.1 M KCl. By controlling the modified region and the concentration of CTAB, the ionic current rectification degree of the nanopore could be tuned over the wide range of 0.2-65 at the voltage of ±0.9 V. The mechanism of the changes in current rectification behavior was analyzed by numerically solving the Poison-Nernst-Planck (PNP) equations.