Jump to main content
Jump to site search


Concentration Independent Micro/Nanofluidic Active Diode using Asymmetric Ion Concentration Polarization Layer

Abstract

Over the past decade, a nanofluidic diode which rectifies ionic currents (i.e. greater current in one direction than in the opposite direction) has been drawn significant attentions in biomolecular sensing, switching and energy harvesting device. For obtaining the current rectification, the conventional nanofluidic diodes have utilized the complex nanoscale asymmetry of physicochemical properties such as nanochannel geometry, surface charge density, and reservoir concentrations, etc. In order to avoid a sophisticated nano-asymmetry, a micro/nanofluidic diode using a microscale asymmetry has been recently introduced, but their diodic performance was still impeded by (i) a low (even no) rectification effect at physiological concentrations over 100 mM and strong dependency on the bulk concentration (ii) only possessing passively predefined rectification factor. Here, we demonstrated the new class of micro/nanofluidic diode that had an ideal perm-selective nanoporous membrane, based on ion concentration polarization (ICP) phenomenon. Thin side-microchannels installed near a nanojunction played as the mitigator of amplified electrokinetic flows generated by ICP and induced a convective salt transfer to the nanoporous membrane, leading to actively controlled micro-scale asymmetry. Using the device, the current rectifications were successfully demonstrated at the wide range of electrolytic concentration (10-5 M~ 3 M) as a function of the fluidic resistance of the side-microchannels. Noteworthly, it was confirmed that the rectification factors were independent from the bulk concentration due to the ideal perm-selectivity. Moreover, the rectification of presenting diode was actively controlled by adjusting external convective flows, while that of previous diode was passively-determined by invariant nanoscale asymmetry.

Back to tab navigation
Please wait while Download options loads

Supplementary files

Publication details

The article was received on 23 Mar 2017, accepted on 18 May 2017 and first published on 19 May 2017


Article type: Paper
DOI: 10.1039/C7NR02075A
Citation: Nanoscale, 2017, Accepted Manuscript
  •   Request permissions

    Concentration Independent Micro/Nanofluidic Active Diode using Asymmetric Ion Concentration Polarization Layer

    H. Lee, J. Kim, H. Kim, H. Kim, H. Lee and S. J. Kim, Nanoscale, 2017, Accepted Manuscript , DOI: 10.1039/C7NR02075A

Search articles by author