Journal
ANALYTICAL CHEMISTRY
Volume 84, Issue 1, Pages 267-274Publisher
AMER CHEMICAL SOC
DOI: 10.1021/ac202501v
Keywords
-
Categories
Funding
- National Science Foundation [CHE-0750295, CHE-0832651]
- Project HLRB pr26wo
- Direct For Mathematical & Physical Scien
- Division Of Chemistry [0832651] Funding Source: National Science Foundation
Ask authors/readers for more resources
We study ionic current rectification observed in a nanofluidic device with a nanofunnel positioned between two straight nanochannels. Ion transport is simulated by resolving the coupled three-dimensional Nernst-Planck, Poisson, and Navier-Stokes equations. In the modeled system, the electric double layer extends into the channel, and consequently, the funnel tip exhibits charge-selective properties, which results in the formation of enriched and depleted concentration polarization (CP) zones within the nanofunnel in the high- and low-conductance states, respectively. This scenario is similar to the one observed for ion transport through a charged conical nano-pore connecting two macroscopic reservoirs. However, the presence of the adjacent straight nanochannels allows the CP zones to propagate out of the funnel into the adjoining channels. The condition for propagation of the CP zones is determined by several parameters, including the electroosmotic flow velocity. We demonstrate that in the high-conductance regime the modeled system is characterized by increased ionic concentrations in the entire cathodic nanochannel, whereas in the low-conductance state the depleted CP zone does not propagate out of the funnel and remains localized. The required three-dimensional modeling scheme is implemented on a parallel computational platform, is general as well as numerically efficient, and will be useful in the study of more advanced nanofluidic device designs for tailoring ionic current rectification.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available