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Title: Scanning Ion Conductance Microscopy of Nafion-Modified Nanopores
Single nanopores in silicon nitride membranes are asymmetrically modified with Nafion and investigated with scanning ion conductance microscopy, where Nafion alters local ion concentrations at the nanopore. Effects of applied transmembrane potentials on local ion concentrations are examined, with the Nafion film providing a reservoir of cations in close proximity to the nanopore. Fluidic diodes based on ion concentration polarization are observed in the current-voltage response of the nanopore and in approach curves of SICM nanopipette in the vicinity of the nanopore. Experimental results are supported with finite element method simulations that detail ion depletion and enrichment of the nanopore/Nafion/nanopipette environment.  more » « less
Award ID(s):
1803002 2220830
PAR ID:
10438174
Author(s) / Creator(s):
; ;
Publisher / Repository:
IOPScience
Date Published:
Journal Name:
Journal of The Electrochemical Society
Volume:
170
Issue:
6
ISSN:
0013-4651
Page Range / eLocation ID:
066510
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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