In-Situ Imaging of Chloride Ions at the Metal/Solution Interface by Scanning Combination Microelectrodes.
In-Situ Imaging of Chloride Ions at the Metal/Solution
Interface by Scanning Combination Microelectrodes.
(931 K)
Lin, C. J.; Du, R. G.; Nguyen, T.
Corrosion, Vol. 56, No. 1, 41-47, January 2000.
Keywords:
chloride ion; ion selective microelectrode; imaging;
interface; microelectrode; solution/metal
Abstract:
Combination solid silver-silver (Ag/AgCl) and liquid
membrane Cl- ion-selective microelectrodes have been
designed and constructed. These microelectrodes, which
have a micrometer size tip, contain two compartments,
one serves as the reference electrode and the other as
the Cl- ion-selective electrode. The microelectrodes
have been used to map in situ Cl- ion distribution in
several localized corrosion systems. When used with a
computerized scanning stage, the microelectrodes can
provide information on the distribution of Cl- ions near
the metal/electrolyte interface. Cl- ions were observed
to migrate towards, and accumulate near, the anodic
region forming a "chloride ion rich island" on the metal
surface. Scanning combination Cl- ion-selective
microelectrodes may provide a useful tool for
mechanistic studies of localized corrosion.
Building and Fire Research Laboratory
National Institute of Standards and Technology
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